1
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Hao X, Zhang T, Niu M, Han X, Yang H, Zhang Q, Hou Y, Grazioli C, Liu L, Qiao J, Wang Y. Selective Formation of Homochiral Dimers by Intermolecular Charge Transfer on a hBN Nanomesh. ACS Nano 2024; 18:11933-11940. [PMID: 38663413 DOI: 10.1021/acsnano.4c01844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C57H48N4, SBM) using scanning tunneling microscopy. When adsorbed onto the hBN/Rh(111) nanomesh, these molecules demonstrate homochiral recognition, leading to a selective formation of homochiral dimers. Further tip manipulation experiments reveal that the chiral dimers are stable and primarily controlled by strong intermolecular interactions. Density functional theory (DFT) calculations supported that the chiral recognition of SBM molecules is governed by the intermolecular charge transfer mechanism, different from the common steric hindrance effect. This study emphasizes the importance of intermolecular charge transfer interactions, offering valuable insights into the chiral recognition of a simple bimolecular system. These findings hold significance for the future advancement in chirality-based electronic sensors and pharmaceuticals, where the chirality of molecules can impact their properties.
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Affiliation(s)
- Xiaoyu Hao
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Teng Zhang
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Mengmeng Niu
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Xu Han
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Huixia Yang
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Quanzhen Zhang
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Yanhui Hou
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Cesare Grazioli
- IOM-CNR, Laboratorio TASC, Sincrotrone Trieste, Trieste 34149, Italy
| | - Liwei Liu
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Jingsi Qiao
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
| | - Yeliang Wang
- School of Integrated Circuits and Electronics & Yangtze Delta Region Academy, Beijing Institute of Technology (BIT), Beijing 100081, China
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2
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Gao W, Zhi G, Zhou M, Niu T. Growth of Single Crystalline 2D Materials beyond Graphene on Non-metallic Substrates. Small 2024:e2311317. [PMID: 38712469 DOI: 10.1002/smll.202311317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 03/14/2024] [Indexed: 05/08/2024]
Abstract
The advent of 2D materials has ushered in the exploration of their synthesis, characterization and application. While plenty of 2D materials have been synthesized on various metallic substrates, interfacial interaction significantly affects their intrinsic electronic properties. Additionally, the complex transfer process presents further challenges. In this context, experimental efforts are devoted to the direct growth on technologically important semiconductor/insulator substrates. This review aims to uncover the effects of substrate on the growth of 2D materials. The focus is on non-metallic substrate used for epitaxial growth and how this highlights the necessity for phase engineering and advanced characterization at atomic scale. Special attention is paid to monoelemental 2D structures with topological properties. The conclusion is drawn through a discussion of the requirements for integrating 2D materials with current semiconductor-based technology and the unique properties of heterostructures based on 2D materials. Overall, this review describes how 2D materials can be fabricated directly on non-metallic substrates and the exploration of growth mechanism at atomic scale.
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Affiliation(s)
- Wenjin Gao
- Tianmushan Laboratory, Hangzhou, 310023, China
- Hangzhou International Innovation Institute, Beihang University, Hangzhou, 311115, China
- School of Physics, Beihang University, Beijing, 100191, China
| | | | - Miao Zhou
- Tianmushan Laboratory, Hangzhou, 310023, China
- Hangzhou International Innovation Institute, Beihang University, Hangzhou, 311115, China
- School of Physics, Beihang University, Beijing, 100191, China
| | - Tianchao Niu
- Hangzhou International Innovation Institute, Beihang University, Hangzhou, 311115, China
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3
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Bui HT, Wolf C, Wang Y, Haze M, Ardavan A, Heinrich AJ, Phark SH. All-Electrical Driving and Probing of Dressed States in a Single Spin. ACS Nano 2024. [PMID: 38698541 DOI: 10.1021/acsnano.4c00196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
The subnanometer distance between tip and sample in a scanning tunneling microscope (STM) enables the application of very large electric fields with a strength as high as ∼1 GV/m. This has allowed for efficient electrical driving of Rabi oscillations of a single spin on a surface at a moderate radiofrequency (RF) voltage on the order of tens of millivolts. Here, we demonstrate the creation of dressed states of a single electron spin localized in the STM tunnel junction by using resonant RF driving voltages. The read-out of these dressed states was achieved all electrically by a weakly coupled probe spin. Our work highlights the strength of the atomic-scale geometry inherent to the STM that facilitates the creation and control of dressed states, which are promising for the design of atomic scale quantum devices using individual spins on surfaces.
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Affiliation(s)
- Hong T Bui
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Department of Physics, Ewha Womans University, Seoul 03760, Korea
| | - Christoph Wolf
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Ewha Womans University, Seoul 03760, Korea
| | - Yu Wang
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Ewha Womans University, Seoul 03760, Korea
| | - Masahiro Haze
- The Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
| | - Arzhang Ardavan
- CAESR, Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Andreas J Heinrich
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Department of Physics, Ewha Womans University, Seoul 03760, Korea
| | - Soo-Hyon Phark
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Ewha Womans University, Seoul 03760, Korea
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4
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Amini M, Fumega AO, González-Herrero H, Vaňo V, Kezilebieke S, Lado JL, Liljeroth P. Atomic-Scale Visualization of Multiferroicity in Monolayer NiI 2. Adv Mater 2024; 36:e2311342. [PMID: 38241258 DOI: 10.1002/adma.202311342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 01/09/2024] [Indexed: 01/21/2024]
Abstract
Progress in layered van der Waals materials has resulted in the discovery of ferromagnetic and ferroelectric materials down to the monolayer limit. Recently, evidence of the first purely 2D multiferroic material was reported in monolayer NiI2. However, probing multiferroicity with scattering-based and optical bulk techniques is challenging on 2D materials, and experiments on the atomic scale are needed to fully characterize the multiferroic order at the monolayer limit. Here, scanning tunneling microscopy (STM) supported by density functional theory (DFT) calculations is used to probe and characterize the multiferroic order in monolayer NiI2. It is demonstrated that the type-II multiferroic order displayed by NiI2, arising from the combination of a magnetic spin spiral order and a strong spin-orbit coupling, allows probing the multiferroic order in the STM experiments. Moreover, the magnetoelectric coupling of NiI2 is directly probed by external electric field manipulation of the multiferroic domains. The findings establish a novel point of view to analyze magnetoelectric effects at the microscopic level, paving the way toward engineering new multiferroic orders in van der Waals materials and their heterostructures.
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Affiliation(s)
- Mohammad Amini
- Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland
| | - Adolfo O Fumega
- Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland
| | - Héctor González-Herrero
- Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, E-28049, Spain
| | - Viliam Vaňo
- Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland
- Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Shawulienu Kezilebieke
- Department of Physics, Department of Chemistry and Nanoscience Center, University of Jyväskylä, Jyväskylä, FI-40014, Finland
| | - Jose L Lado
- Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland
| | - Peter Liljeroth
- Department of Applied Physics, Aalto University, Aalto, FI-00076, Finland
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5
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Kurki L, Oinonen N, Foster AS. Automated Structure Discovery for Scanning Tunneling Microscopy. ACS Nano 2024; 18:11130-11138. [PMID: 38644571 PMCID: PMC11064214 DOI: 10.1021/acsnano.3c12654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/25/2024] [Accepted: 04/05/2024] [Indexed: 04/23/2024]
Abstract
Scanning tunneling microscopy (STM) with a functionalized tip apex reveals the geometric and electronic structures of a sample within the same experiment. However, the complex nature of the signal makes images difficult to interpret and has so far limited most research to planar samples with a known chemical composition. Here, we present automated structure discovery for STM (ASD-STM), a machine learning tool for predicting the atomic structure directly from an STM image, by building upon successful methods for structure discovery in noncontact atomic force microscopy (nc-AFM). We apply the method on various organic molecules and achieve good accuracy on structure predictions and chemical identification on a qualitative level while highlighting future development requirements for ASD-STM. This method is directly applicable to experimental STM images of organic molecules, making structure discovery available for a wider scanning probe microscopy audience outside of nc-AFM. This work also allows more advanced machine learning methods to be developed for STM structure discovery.
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Affiliation(s)
- Lauri Kurki
- Department
of Applied Physics, Aalto University, Aalto, Espoo 00076, Finland
| | - Niko Oinonen
- Department
of Applied Physics, Aalto University, Aalto, Espoo 00076, Finland
- Nanolayers
Research Computing Ltd., London N12 0HL, U.K.
| | - Adam S. Foster
- Department
of Applied Physics, Aalto University, Aalto, Espoo 00076, Finland
- WPI
Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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6
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Grewal A, Leon CC, Kuhnke K, Kern K, Gunnarsson O. Scanning Tunneling Microscopy for Molecules: Effects of Electron Propagation into Vacuum. ACS Nano 2024. [PMID: 38684019 DOI: 10.1021/acsnano.3c12315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Using scanning tunneling microscopy (STM), we experimentally and theoretically investigate isolated platinum phthalocyanine (PtPc) molecules adsorbed on an atomically thin NaCl(100) film vapor deposited on Au(111). We obtain good agreement between theory and constant-height STM topography. We theoretically examine why strong distortions of STM images occur as a function of distance between the molecule and the STM tip. The images of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) exhibit for increasing distance, significant radial expansion due to electron propagation in the vacuum. Additionally, the imaged angular dependence is substantially distorted. The LUMO image has substantial intensity along the molecular diagonals where PtPc has no atoms. In the electronic transport gap, the image differs drastically from HOMO and LUMO even at energies very close to these orbitals. As the tunneling becomes increasingly off-resonant, the eight angular lobes of the HOMO or of the degenerate LUMOs diminish and reveal four lobes with maxima along the molecular axes, where both, HOMO and LUMO have little or no weight. These images are strongly influenced by low-lying PtPc orbitals that have simple angular structures.
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Affiliation(s)
- Abhishek Grewal
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - Christopher C Leon
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - Klaus Kuhnke
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - Klaus Kern
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
- Institut de Physique, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland
| | - Olle Gunnarsson
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
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7
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Kim L, Scougale WR, Sharma P, Shirato N, Wieghold S, Rose V, Chen W, Balasubramanian G, Chien T. Distinguishing Elements at the Sub-Nanometer Scale on the Surface of a High Entropy Alloy. Adv Mater 2024:e2402442. [PMID: 38682745 DOI: 10.1002/adma.202402442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/17/2024] [Indexed: 05/01/2024]
Abstract
Materials in crystalline form possess translational symmetry (TS) when the unit cell is repeated in real space with long- and short-range orders. The periodic potential in the crystal regulates the electron wave function and results in unique band structures, which further define the physical properties of the materials. Amorphous materials lack TS due to the randomization of distances and arrangements between atoms, causing the electron wave function to lack a well-defined momentum. High entropy materials provide another way to break the TS by randomizing the potential strength at periodic atomic sites. The local elemental distribution has a great impact on physical properties in high entropy materials. It is critical to distinguish elements at the sub-nanometer scale to uncover the correlations between the elemental distribution and the material properties. Here, the use of synchrotron X-ray scanning tunneling microscopy (SX-STM) with sub-nm scale resolution in identifying elements on a high entropy alloy (HEA) surface is demonstrated. By examining the elementally sensitive X-ray absorption spectra with an STM tip to enhance the spatial resolution, the elemental distribution on an HEA's surface at a sub-nm scale is extracted. These results open a pathway towards quantitatively understanding high entropy materials and their material properties.
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Affiliation(s)
- Lauren Kim
- Department of Physics & Astronomy, University of Wyoming, Laramie, WY, 82071, USA
| | - William R Scougale
- Department of Physics & Astronomy, University of Wyoming, Laramie, WY, 82071, USA
| | - Prince Sharma
- Department of Mechanical Engineering & Mechanics, Lehigh University, Bethlehem, PA, 18015, USA
| | - Nozomi Shirato
- Nanoscience and Technology Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Sarah Wieghold
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Volker Rose
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Wei Chen
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Ganesh Balasubramanian
- Department of Mechanical Engineering & Mechanics, Lehigh University, Bethlehem, PA, 18015, USA
| | - TeYu Chien
- Department of Physics & Astronomy, University of Wyoming, Laramie, WY, 82071, USA
- Center for Quantum Information Science & Engineering, University of Wyoming, Laramie, WY, 82071, USA
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8
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Wang H, Ding P, Xia GJ, Zhao X, E W, Yu M, Ma Z, Wang YG, Wang LS, Li J, Yang X. Formation of Supernarrow Borophene Nanoribbons. Angew Chem Int Ed Engl 2024:e202406535. [PMID: 38652809 DOI: 10.1002/anie.202406535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
Borophenes have sparked considerable interest owing to their fascinating physical characteristics and diverse polymorphism. However, borophene nanoribbons (BNRs) with widths less than 2 nm have not been achieved. Herein, we report the experimental realization of supernarrow BNRs. Combining scanning tunneling microscopy imaging with density functional theory modeling and ab initio molecular dynamics simulations, we demonstrate that, under the applied growth conditions, boron atoms can penetrate the outermost layer of Au(111) and form BNRs composed of a pair of zigzag (2,2) boron rows. The BNRs have a width self-contained to ∼1 nm and dipoles at the edges to keep them separated. They are embedded in the outermost Au layer and shielded on top by the evacuated Au atoms, free of the need for post-passivation. Scanning tunneling spectroscopy reveals distinct edge states, primarily attributed to the localized spin at the BNRs' zigzag edges. This work adds a new member to the boron material family and introduces a new physical feature to borophenes.
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Affiliation(s)
- Haochen Wang
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, CHINA
| | - Pengcheng Ding
- Harbin Institute of Technology, School of Chemistry and Chemical Engineering, CHINA
| | - Guang-Jie Xia
- Southern University of Science and Technology, Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry, CHINA
| | - Xiangyun Zhao
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, CHINA
| | - Wenlong E
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, CHINA
| | - Miao Yu
- Harbin Institute of Technology, School of Chemical Engineering and Technology, 92 Xidazhi St., 150001, Harbin, CHINA
| | - Zhibo Ma
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, CHINA
| | - Yang-Gang Wang
- Southern University of Science and Technology, Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry, CHINA
| | - Lai-Sheng Wang
- Brown University, Department of Chemistry, UNITED STATES
| | - Jun Li
- Tsinghua University, Department of Chemistry, CHINA
| | - Xueming Yang
- Dalian Institute of Chemical Physics, State Key Laboratory of Molecular Reaction Dynamics, CHINA
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9
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Zhou X, Jiang T, Tao Y, Ji Y, Wang J, Lai T, Zhong D. Evidence of Ferromagnetism and Ultrafast Dynamics of Demagnetization in an Epitaxial FeCl 2 Monolayer. ACS Nano 2024; 18:10912-10920. [PMID: 38613502 DOI: 10.1021/acsnano.4c01436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2024]
Abstract
The development of two-dimensional (2D) magnetism is driven not only by the interest of low-dimensional physics but also by potential applications in high-density miniaturized spintronic devices. However, 2D materials possessing a ferromagnetic order with a relatively high Curie temperature (Tc) are rare. In this paper, the evidence of ferromagnetism in monolayer FeCl2 on Au(111) surfaces, as well as the interlayer antiferromagnetic coupling of bilayer FeCl2, is characterized by using spin-polarized scanning tunneling microscopy. A Curie temperature (Tc) of ∼147 K is revealed for monolayer FeCl2, based on our static magneto-optical Kerr effect measurements. Furthermore, temperature-dependent magnetization dynamics is investigated by the time-resolved magneto-optical Kerr effect. A transition from one- to two-step demagnetization occurs as the lattice temperature approaches Tc, which supports the Elliott-Yafet spin relaxation mechanism. The findings contribute to a deeper understanding of the underlying mechanisms governing ultrafast magnetization in 2D ferromagnetic materials.
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Affiliation(s)
- Xuhan Zhou
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
- Center for Neutron Science and Technology, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- Guangzhou No. 89 Secondary School, Guangzhou 510520, China
| | - Tianran Jiang
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
| | - Ye Tao
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
- Center for Neutron Science and Technology, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
| | - Yi Ji
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
- Center for Neutron Science and Technology, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
| | - Jingying Wang
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
- Center for Neutron Science and Technology, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
| | - Tianshu Lai
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
| | - Dingyong Zhong
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China
- Center for Neutron Science and Technology, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
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10
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Bühlmeyer H, Talwar T, Eschenbacher R, Barreto J, Hauner J, Knörr L, Steinrück HP, Maier F, Libuda J. Surface Chemistry of a [C 2C 1Im][OTf] (Sub)Wetting Layer on Pt(111): A Combined XPS, IRAS, and STM Study. ACS Appl Mater Interfaces 2024. [PMID: 38652177 DOI: 10.1021/acsami.4c02239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
The concept of a solid catalyst with an ionic liquid layer (SCILL) is a promising approach to improve the selectivity of noble metal catalysts in heterogeneous reactions. In order to understand the origins of this selectivity control, we investigated the growth and thermal stability of ultrathin 1-ethyl-3-methylimidazolium trifluormethanesulfonate [C2C1Im][OTf] films on Pt(111) by infrared reflection absorption spectroscopy (IRAS) and X-ray photoelectron spectroscopy (XPS) in time-resolved and temperature-programmed experiments. We combined these spectroscopy experiments with scanning tunneling microscopy (STM) to obtain detailed insights into the orientation and adsorption geometry of the ions in the first IL layer. Furthermore, we propose a mechanism for the thermal evolution of [C2C1Im][OTf] on Pt(111). We observe an intact IL layer on the surface at temperatures below 200 K. Adsorbed [C2C1Im][OTf] forms islands, which are evenly distributed over the surface. The [OTf]- anion adsorbs via the SO3 group, with the molecular axis perpendicular to the surface. Anions and cations are arranged next to each other, alternating on the Pt(111) surface. Upon heating to 250 K, we observe changes in geometry and structural distribution. Whereas at low temperature, the ions are arranged alternately for electrostatic reasons, this driving force is no longer decisive at 250 K. Here, a phase separation of two different species is discernible in STM. We propose that this effect is due to a surface reaction, which changes the charge of the adsorbates. We assume that the IL starts to decompose at around 250 K, and thus, pristine IL and decomposition products coexist on the surface. Also, IRAS and XPS show indication of IL decomposition. Further heating leads to increased IL decomposition. The reaction products associated with the anions are volatile and leave the surface. In contrast, the cation fragments remain on the surface up to temperatures above 420 K.
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Affiliation(s)
- Hanna Bühlmeyer
- Interface Research and Catalysis, ECRC, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Timo Talwar
- Chair of Physical Chemistry II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Roman Eschenbacher
- Interface Research and Catalysis, ECRC, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Jade Barreto
- Chair of Physical Chemistry II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Jonas Hauner
- Interface Research and Catalysis, ECRC, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Lukas Knörr
- Interface Research and Catalysis, ECRC, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Hans-Peter Steinrück
- Chair of Physical Chemistry II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Florian Maier
- Chair of Physical Chemistry II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Jörg Libuda
- Interface Research and Catalysis, ECRC, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
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11
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Dong J, Inbar HS, Dempsey CP, Engel AN, Palmstrøm CJ. Strain Solitons in an Epitaxially Strained van der Waals-like Material. Nano Lett 2024; 24:4493-4497. [PMID: 38498733 PMCID: PMC11036392 DOI: 10.1021/acs.nanolett.4c00382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/14/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024]
Abstract
Strain solitons are quasi-dislocations that form in van der Waals materials to relieve the energy associated with lattice or rotational mismatch. Novel electronic properties of strain solitons were predicted and observed. To date, strain solitons have been observed only in exfoliated crystals or mechanically strained crystals. The lack of a scalable approach toward the generation of strain solitons poses a significant challenge in the study of and use of their properties. Here, we report the formation of strain solitons with epitaxial growth of bismuth on InSb(111)B by molecular beam epitaxy. The morphology of the strain solitons for films of varying thickness is characterized with scanning tunneling microscopy, and the local strain state is determined from atomic resolution images. Bending in the solitons is attributed to interactions with the interface, and large angle bending is associated with edge dislocations. Our results enable the scalable generation of strain solitons.
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Affiliation(s)
- Jason
T. Dong
- Materials
Department, University of California, Santa Barbara, California 93106, United States
| | - Hadass S. Inbar
- Materials
Department, University of California, Santa Barbara, California 93106, United States
| | - Connor P. Dempsey
- Deparment
of Electrical and Computer Engineering, University of California, Santa
Barbara, California 93106, United States
| | - Aaron N. Engel
- Materials
Department, University of California, Santa Barbara, California 93106, United States
| | - Christopher J. Palmstrøm
- Materials
Department, University of California, Santa Barbara, California 93106, United States
- Deparment
of Electrical and Computer Engineering, University of California, Santa
Barbara, California 93106, United States
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12
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Krajňák T, Stará V, Procházka P, Planer J, Skála T, Blatnik M, Čechal J. Robust Dipolar Layers between Organic Semiconductors and Silver for Energy-Level Alignment. ACS Appl Mater Interfaces 2024; 16:18099-18111. [PMID: 38551398 PMCID: PMC11009919 DOI: 10.1021/acsami.3c18697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 03/13/2024] [Accepted: 03/13/2024] [Indexed: 04/12/2024]
Abstract
The interface between a metal electrode and an organic semiconductor (OS) layer has a defining role in the properties of the resulting device. To obtain the desired performance, interlayers are introduced to modify the adhesion and growth of OS and enhance the efficiency of charge transport through the interface. However, the employed interlayers face common challenges, including a lack of electric dipoles to tune the mutual position of energy levels, being too thick for efficient electronic transport, or being prone to intermixing with subsequently deposited OS layers. Here, we show that monolayers of 1,3,5-tris(4-carboxyphenyl)benzene (BTB) with fully deprotonated carboxyl groups on silver substrates form a compact layer resistant to intermixing while capable of mediating energy-level alignment and showing a large insensitivity to substrate termination. Employing a combination of surface-sensitive techniques, i.e., low-energy electron microscopy and diffraction, X-ray photoelectron spectroscopy, and scanning tunneling microscopy, we have comprehensively characterized the compact layer and proven its robustness against mixing with the subsequently deposited organic semiconductor layer. Density functional theory calculations show that the robustness arises from a strong interaction of carboxylate groups with the Ag surface, and thus, the BTB in the first layer is energetically favored. Synchrotron radiation photoelectron spectroscopy shows that this layer displays considerable electrical dipoles that can be utilized for work function engineering and electronic alignment of molecular frontier orbitals with respect to the substrate Fermi level. Our work thus provides a widely applicable molecular interlayer and general insights necessary for engineering of charge injection layers for efficient organic electronics.
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Affiliation(s)
- Tomáš Krajňák
- CEITEC—Central
European Institute of Technology, Brno University
of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Veronika Stará
- CEITEC—Central
European Institute of Technology, Brno University
of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Pavel Procházka
- CEITEC—Central
European Institute of Technology, Brno University
of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Jakub Planer
- CEITEC—Central
European Institute of Technology, Brno University
of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Tomáš Skála
- Department
of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague 8, Czech Republic
| | - Matthias Blatnik
- CEITEC—Central
European Institute of Technology, Brno University
of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Jan Čechal
- CEITEC—Central
European Institute of Technology, Brno University
of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
- Institute
of Physical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno, Czech Republic
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13
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Cahlík A, Ondráček M, Wäckerlin C, Solé AP, Siri O, Švec M, Jelínek P. Light-Controlled Multiconfigurational Conductance Switching in a Single 1D Metal-Organic Wire. ACS Nano 2024; 18:9576-9583. [PMID: 38518264 PMCID: PMC10993641 DOI: 10.1021/acsnano.3c12909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/10/2024] [Accepted: 03/14/2024] [Indexed: 03/24/2024]
Abstract
Precise control of multiple spin states on the atomic scale presents a promising avenue for designing and realizing magnetic switches. Despite substantial progress in recent decades, the challenge of achieving control over multiconfigurational reversible switches in low-dimensional nanostructures persists. Our work demonstrates multiple, fully reversible plasmon-driven spin-crossover switches in a single π-d metal-organic chain suspended between two electrodes. The plasmonic nanocavity stimulated by external visible light allows for reversible spin crossover between low- and high-spin states of different cobalt centers within the chain. We show that the distinct spin configurations remain stable for minutes under cryogenic conditions and can be nonperturbatively detected by conductance measurements. This multiconfigurational plasmon-driven spin-crossover demonstration extends the available toolset for designing optoelectrical molecular devices based on SCO compounds.
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Affiliation(s)
- Aleš Cahlík
- Institute
of Physics of the Czech Academy of Sciences, Prague, 16200, Czech Republic
- Department
of Physics, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Martin Ondráček
- Institute
of Physics of the Czech Academy of Sciences, Prague, 16200, Czech Republic
| | - Christian Wäckerlin
- Institute
of Physics of the Czech Academy of Sciences, Prague, 16200, Czech Republic
- Institute
of Physics, École Polytechnique Fédérale de Lausanne
(EPFL), Station 3, CH-1015 Lausanne, Switzerland
- Laboratory
for X-ray Nanoscience and Technologies, Paul-Scherrer-Institut (PSI), CH-5232 Villigen, PSI, Switzerland
| | - Andres Pinar Solé
- Institute
of Physics of the Czech Academy of Sciences, Prague, 16200, Czech Republic
| | - Olivier Siri
- Aix
Marseille Université, CINaM UMR 7325 CNRS, Campus de Luminy, 13288 Marseille
cedex 09, France
| | - Martin Švec
- Institute
of Physics of the Czech Academy of Sciences, Prague, 16200, Czech Republic
| | - Pavel Jelínek
- Institute
of Physics of the Czech Academy of Sciences, Prague, 16200, Czech Republic
- Regional
Centre of Advanced Technologies and Materials, Czech Advanced Technology
and Research Institute (CATRIN), Palacký
University Olomouc, 78371 Olomouc, Czech Republic
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14
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Trainer D, Lee AT, Sarkar S, Singh V, Cheng X, Dandu NK, Latt KZ, Wang S, Ajayi TM, Premarathna S, Facemyer D, Curtiss LA, Ulloa SE, Ngo AT, Masson E, Hla SW. 2D Ionic Liquid-Like State of Charged Rare-Earth Clusters on a Metal Surface. Adv Sci (Weinh) 2024; 11:e2308813. [PMID: 38268161 PMCID: PMC10987101 DOI: 10.1002/advs.202308813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/16/2023] [Indexed: 01/26/2024]
Abstract
Rare-earth complexes are vital for separation chemistry and useful in many advanced applications including emission and energy upconversion. Here, 2D rare-earth clusters having net charges are formed on a metal surface, enabling investigations of their structural and electronic properties on a one-cluster-at-a-time basis using scanning tunneling microscopy. While these ionic complexes are highly mobile on the surface at ≈100 K, their mobility is greatly reduced at 5 K and reveals stable and self-limiting clusters. In each cluster, a pair of charged rare-earth complexes formed by electrostatic and dispersive interactions act as a basic unit, and the clusters are chiral. Unlike other non-ionic molecular clusters formed on the surfaces, these rare-earth clusters show mechanical stability. Moreover, their high mobility on the surface suggests that they are in a 2D liquid-like state.
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Affiliation(s)
- Daniel Trainer
- Nanoscience and Technology DivisionArgonne National laboratoryLemontIL60439USA
| | - Alex Taekyung Lee
- Chemical Engineering DepartmentUniversity of Illinois at ChicagoChicagoIL60608USA
- Materials Science DivisionArgonne National laboratoryLemontIL60439USA
| | - Sanjoy Sarkar
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - Vijay Singh
- Chemical Engineering DepartmentUniversity of Illinois at ChicagoChicagoIL60608USA
- Materials Science DivisionArgonne National laboratoryLemontIL60439USA
- Present address:
Department of PhysicsGITAM School of ScienceBengaluruKarnataka561203India
| | - Xinyue Cheng
- Department of Chemistry and BiochemistryOhio UniversityAthensOH45701USA
| | - Naveen K. Dandu
- Chemical Engineering DepartmentUniversity of Illinois at ChicagoChicagoIL60608USA
- Materials Science DivisionArgonne National laboratoryLemontIL60439USA
| | - Kyaw Zin Latt
- Nanoscience and Technology DivisionArgonne National laboratoryLemontIL60439USA
| | - Shaoze Wang
- Nanoscience and Technology DivisionArgonne National laboratoryLemontIL60439USA
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - Tolulope Michael Ajayi
- Nanoscience and Technology DivisionArgonne National laboratoryLemontIL60439USA
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - Sineth Premarathna
- Nanoscience and Technology DivisionArgonne National laboratoryLemontIL60439USA
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - David Facemyer
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - Larry A. Curtiss
- Materials Science DivisionArgonne National laboratoryLemontIL60439USA
| | - Sergio E. Ulloa
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
| | - Anh T. Ngo
- Chemical Engineering DepartmentUniversity of Illinois at ChicagoChicagoIL60608USA
- Materials Science DivisionArgonne National laboratoryLemontIL60439USA
| | - Eric Masson
- Department of Chemistry and BiochemistryOhio UniversityAthensOH45701USA
| | - Saw Wai Hla
- Nanoscience and Technology DivisionArgonne National laboratoryLemontIL60439USA
- Nanoscale and Quantum Phenomena Instituteand Department of Physics and AstronomyOhio UniversityAthensOH45701USA
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15
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Merino-Diez N, Amador R, Stolz ST, Passerone D, Widmer R, Gröning O. Asymmetric Molecular Adsorption and Regioselective Bond Cleavage on Chiral PdGa Crystals. Adv Sci (Weinh) 2024; 11:e2309081. [PMID: 38353319 DOI: 10.1002/advs.202309081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/22/2024] [Indexed: 04/25/2024]
Abstract
Homogenous enantioselective catalysis is nowadays the cornerstone in the manufacturing of enantiopure substances, but its technological implementation suffers from well-known impediments like the lack of endurable catalysts exhibiting long-term stability. The catalytically active intermetallic compound Palladium-Gallium (PdGa), conserving innate bulk chirality on its surfaces, represent a promising system to study asymmetric chemical reactions by heterogeneous catalysis, with prospective relevance for industrial processes. Here, this work investigates the adsorption of 10,10'-dibromo-9,9'-bianthracene (DBBA) on the PdGa:A(1 ¯ 1 ¯ 1 ¯ $\bar{1}\bar{1}\bar{1}$ ) Pd3-terminated surface by means of scanning tunneling microscopy (STM) and spectroscopy (STS). A highly enantioselective adsorption of the molecule evolving into a near 100% enantiomeric excess below room temperature is observed. This exceptionally high enantiomeric excess is attributed to temperature activated conversion of the S to the R chiral conformer. Tip-induced bond cleavage of the R conformer shows a very high regioselectivity of the DBBA debromination. The experimental results are interpreted by density functional theory atomistic simulations. This work extends the knowledge of chirality transfer onto the enantioselective adsorption of non-planar molecules and manifests the ensemble effect of PdGa surfaces resulting in robust regioselective debromination.
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Affiliation(s)
- Nestor Merino-Diez
- Nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
| | - Raymond Amador
- Nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
| | - Samuel T Stolz
- Nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
| | - Daniele Passerone
- Nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
| | - Roland Widmer
- Nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
| | - Oliver Gröning
- Nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
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16
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Zhang Z, Gao Y, Yi Z, Zhang C, Xu W. Separation of Halogen Atoms by Sodium from Dehalogenative Reactions on a Au(111) Surface. ACS Nano 2024; 18:9082-9091. [PMID: 38466951 DOI: 10.1021/acsnano.3c12949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
On-surface dehalogenative reactions have been promising in the construction of nanostructures with diverse morphologies and intriguing electronic properties, while halogen (X), as the main byproduct, often impedes the formation of extended nanostructures and property characterization, and the reaction usually requires high C-X activation temperatures, especially on relatively inert Au(111). Enormous efforts in precursor design, halogen-to-halide conversion, and the introduction of extrinsic metal atoms have been devoted to either eliminating dissociated halogens or reducing reaction barriers. However, it is still challenging to separate halogens from molecular systems while facilitating C-X activation under mild conditions. Herein, a versatile halogen separation strategy has been developed based on the introduction of extrinsic sodium (Na) into dehalogenative reactions on Au(111) as model systems that both isolates the dissociated halogens and facilitates the C-Br activation under mild conditions. Moreover, the combination of scanning tunneling microscopy imaging and density functional theory calculations reveals the formation of sodium halides (NaX) from halogens in these separation processes as well as the reduction in reaction temperatures and barriers, demonstrating the versatility of extrinsic sodium as an effective "cleaner" and "dehalogenator" of surface halogens. Our study demonstrates a valuable strategy to facilitate the on-surface dehalogenative reactions, which will assist in the precise fabrication of low-dimensional carbon nanostructures.
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Affiliation(s)
- Zhaoyu Zhang
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Yuhong Gao
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Zewei Yi
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Chi Zhang
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
| | - Wei Xu
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai 201804, People's Republic of China
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17
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Zhou H, Liang K, Bi L, Shi Y, Wang Z, Li S. Spotlight: Visualization of Moiré Quantum Phenomena in Transition Metal Dichalcogenide with Scanning Tunneling Microscopy. ACS Appl Electron Mater 2024; 6:1530-1541. [PMID: 38558951 PMCID: PMC10976882 DOI: 10.1021/acsaelm.3c01328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 04/04/2024]
Abstract
Transition metal dichalcogenide (TMD) moiré superlattices have emerged as a significant area of study in condensed matter physics. Thanks to their superior optical properties, tunable electronic band structure, strong Coulomb interactions, and quenched electron kinetic energy, they offer exciting avenues to explore correlated quantum phenomena, topological properties, and light-matter interactions. In recent years, scanning tunneling microscopy (STM) has made significant impacts on the study of these fields by enabling intrinsic surface visualization and spectroscopic measurements with unprecedented atomic scale detail. Here, we spotlight the key findings and innovative developments in imaging and characterization of TMD heterostructures via STM, from its initial implementation on the in situ grown sample to the latest photocurrent tunneling microscopy. The evolution in sample design, progressing from a conductive to an insulating substrate, has not only expanded our control over TMD moiré superlattices but also promoted an understanding of their structures and strongly correlated properties, such as the structural reconstruction and formation of generalized two-dimensional Wigner crystal states. In addition to highlighting recent advancements, we outline upcoming challenges, suggest the direction of future research, and advocate for the versatile use of STM to further comprehend and manipulate the quantum dynamics in TMD moiré superlattices.
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Affiliation(s)
- Hao Zhou
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0309, United States
- Program
in Materials Science and Engineering, University
of California, San Diego, La Jolla, California 92093-0418, United States
| | - Kangkai Liang
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0309, United States
- Program
in Materials Science and Engineering, University
of California, San Diego, La Jolla, California 92093-0418, United States
| | - Liya Bi
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0309, United States
- Program
in Materials Science and Engineering, University
of California, San Diego, La Jolla, California 92093-0418, United States
| | - Yueqing Shi
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0309, United States
| | - Zihao Wang
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0309, United States
- School
of Physics, Nankai University, Tianjin 300071, China
| | - Shaowei Li
- Department
of Chemistry and Biochemistry, University
of California, San Diego, La Jolla, California 92093-0309, United States
- Program
in Materials Science and Engineering, University
of California, San Diego, La Jolla, California 92093-0418, United States
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18
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Pitters J, Croshaw J, Achal R, Livadaru L, Ng S, Lupoiu R, Chutora T, Huff T, Walus K, Wolkow RA. Atomically Precise Manufacturing of Silicon Electronics. ACS Nano 2024; 18:6766-6816. [PMID: 38376086 PMCID: PMC10919096 DOI: 10.1021/acsnano.3c10412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 02/01/2024] [Accepted: 02/06/2024] [Indexed: 02/21/2024]
Abstract
Atomically precise manufacturing (APM) is a key technique that involves the direct control of atoms in order to manufacture products or components of products. It has been developed most successfully using scanning probe methods and has received particular attention for developing atom scale electronics with a focus on silicon-based systems. This review captures the development of silicon atom-based electronics and is divided into several sections that will cover characterization and atom manipulation of silicon surfaces with scanning tunneling microscopy and atomic force microscopy, development of silicon dangling bonds as atomic quantum dots, creation of atom scale devices, and the wiring and packaging of those circuits. The review will also cover the advance of silicon dangling bond logic design and the progress of silicon quantum atomic designer (SiQAD) simulators. Finally, an outlook of APM and silicon atom electronics will be provided.
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Affiliation(s)
- Jason Pitters
- Nanotechnology
Research Centre, National Research Council
of Canada, Edmonton, Alberta T6G 2M9, Canada
| | - Jeremiah Croshaw
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Roshan Achal
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Quantum
Silicon Inc., Edmonton, Alberta T6G 2M9, Canada
| | - Lucian Livadaru
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Quantum
Silicon Inc., Edmonton, Alberta T6G 2M9, Canada
| | - Samuel Ng
- Department
of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Robert Lupoiu
- School
of Engineering, Stanford University, Stanford, California 94305, United States
| | - Taras Chutora
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Taleana Huff
- Canadian
Bank Note Company, Ottawa, Ontario K1Z 1A1, Canada
| | - Konrad Walus
- Department
of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Robert A. Wolkow
- Department
of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Quantum
Silicon Inc., Edmonton, Alberta T6G 2M9, Canada
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19
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Stock TJZ, Warschkow O, Constantinou PC, Bowler DR, Schofield SR, Curson NJ. Single-Atom Control of Arsenic Incorporation in Silicon for High-Yield Artificial Lattice Fabrication. Adv Mater 2024:e2312282. [PMID: 38380859 DOI: 10.1002/adma.202312282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/29/2024] [Indexed: 02/22/2024]
Abstract
Artificial lattices constructed from individual dopant atoms within a semiconductor crystal hold promise to provide novel materials with tailored electronic, magnetic, and optical properties. These custom-engineered lattices are anticipated to enable new, fundamental discoveries in condensed matter physics and lead to the creation of new semiconductor technologies including analog quantum simulators and universal solid-state quantum computers. This work reports precise and repeatable, substitutional incorporation of single arsenic atoms into a silicon lattice. A combination of scanning tunneling microscopy hydrogen resist lithography and a detailed statistical exploration of the chemistry of arsine on the hydrogen-terminated silicon (001) surface are employed to show that single arsenic dopants can be deterministically placed within four silicon lattice sites and incorporated with 97 ± 2% yield. These findings bring closer to the ultimate frontier in semiconductor technology: the deterministic assembly of atomically precise dopant and qubit arrays at arbitrarily large scales.
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Affiliation(s)
- Taylor J Z Stock
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
- Department of Electronic and Electrical Engineering, University College London, London, WC1E 7JE, UK
| | - Oliver Warschkow
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
| | - Procopios C Constantinou
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
| | - David R Bowler
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK
| | - Steven R Schofield
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK
| | - Neil J Curson
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
- Department of Electronic and Electrical Engineering, University College London, London, WC1E 7JE, UK
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20
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Baumann S, McMurtrie G, Hänze M, Betz N, Arnhold L, Malavolti L, Loth S. An Atomic-Scale Vector Network Analyzer. Small Methods 2024:e2301526. [PMID: 38381093 DOI: 10.1002/smtd.202301526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/16/2024] [Indexed: 02/22/2024]
Abstract
Electronic devices have been ever-shrinking toward atomic dimensions and have reached operation frequencies in the GHz range, thereby outperforming most conventional test equipment, such as vector network analyzers (VNA). Here the capabilities of a VNA on the atomic scale in a scanning tunneling microscope are implemented. Nonlinearities present in the voltage-current characteristic of atoms and nanostructures for phase-resolved microwave spectroscopy with unprecedented spatial resolution at GHz frequencies are exploited. The amplitude and phase response up to 9.3 GHz is determined, which permits accurate de-embedding of the transmission line and application of distortion-corrected waveforms in the tunnel junction itself. This enables quantitative characterization of the complex-valued admittance of individual magnetic iron atoms which show a lowpass response with a magnetic-field-tunable cutoff frequency.
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Affiliation(s)
- Susanne Baumann
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany
| | - Gregory McMurtrie
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany
| | - Max Hänze
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
| | - Nicolaj Betz
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany
| | - Lukas Arnhold
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany
| | - Luigi Malavolti
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
| | - Sebastian Loth
- Institute for Functional Matter and Quantum Technologies, University of Stuttgart, 70569, Stuttgart, Germany
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
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21
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Seo D, Seong S, Kim H, Oh HS, Lee JH, Kim H, Kim YO, Maeda S, Chikami S, Hayashi T, Noh J. Molecular Self-Assembly and Adsorption Structure of 2,2'-Dipyrimidyl Disulfides on Au(111) Surfaces. Molecules 2024; 29:846. [PMID: 38398598 PMCID: PMC10892263 DOI: 10.3390/molecules29040846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/08/2024] [Accepted: 02/12/2024] [Indexed: 02/25/2024] Open
Abstract
The effects of solution concentration and pH on the formation and surface structure of 2-pyrimidinethiolate (2PymS) self-assembled monolayers (SAMs) on Au(111) via the adsorption of 2,2'-dipyrimidyl disulfide (DPymDS) were examined using scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). STM observations revealed that the formation and structural order of 2PymS SAMs were markedly influenced by the solution concentration and pH. 2PymS SAMs formed in a 0.01 mM ethanol solution were mainly composed of a more uniform and ordered phase compared with those formed in 0.001 mM or 1 mM solutions. SAMs formed in a 0.01 mM solution at pH 2 were composed of a fully disordered phase with many irregular and bright aggregates, whereas SAMs formed at pH 7 had small ordered domains and many bright islands. As the solution pH increased from pH 7 to pH 12, the surface morphology of 2PymS SAMs remarkably changed from small ordered domains to large ordered domains, which can be described as a (4√2 × 3)R51° packing structure. XPS measurements clearly showed that the adsorption of DPymDS on Au(111) resulted in the formation of 2PymS (thiolate) SAMs via the cleavage of the disulfide (S-S) bond in DPymDS, and most N atoms in the pyrimidine rings existed in the deprotonated form. The results herein will provide a new insight into the molecular self-assembly behaviors and adsorption structures of DPymDS molecules on Au(111) depending on solution concentration and pH.
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Affiliation(s)
- Dongjin Seo
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Sicheon Seong
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Haeri Kim
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Hyun Su Oh
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Jun Hyeong Lee
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Hongki Kim
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Yeon O Kim
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
| | - Shoichi Maeda
- Department of Materials Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan; (S.M.); (S.C.)
| | - Shunta Chikami
- Department of Materials Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan; (S.M.); (S.C.)
| | - Tomohiro Hayashi
- Department of Materials Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan; (S.M.); (S.C.)
| | - Jaegeun Noh
- Department of Chemistry, Hanyang University, Seoul 04763, Republic of Korea; (D.S.); (S.S.); (H.K.); (H.S.O.); (J.H.L.); (H.K.); (Y.O.K.)
- Department of Materials Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan; (S.M.); (S.C.)
- Research Institute for Convergence of Basic Science, Hanyang University, Seoul 04763, Republic of Korea
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22
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van Weerdenburg WJ, Osterhage H, Christianen R, Junghans K, Domínguez E, Kappen HJ, Khajetoorians AA. Stochastic Syncing in Sinusoidally Driven Atomic Orbital Memory. ACS Nano 2024; 18:4840-4846. [PMID: 38291572 PMCID: PMC10867893 DOI: 10.1021/acsnano.3c09635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 01/11/2024] [Accepted: 01/25/2024] [Indexed: 02/01/2024]
Abstract
Stochastically fluctuating multiwell systems are a promising route toward physical implementations of energy-based machine learning and neuromorphic hardware. One of the challenges is finding tunable material platforms that exhibit such multiwell behavior and understanding how complex dynamic input signals influence their stochastic response. One such platform is the recently discovered atomic Boltzmann machine, where each stochastic unit is represented by a binary orbital memory state of an individual atom. Here, we investigate the stochastic response of binary orbital memory states to sinusoidal input voltages. Using scanning tunneling microscopy, we investigated orbital memory derived from individual Fe and Co atoms on black phosphorus. We quantify the state residence times as a function of various input parameters such as frequency, amplitude, and offset voltage. The state residence times for both species, when driven by a sinusoidal signal, exhibit synchronization that can be quantitatively modeled by a Poisson process based on the switching rates in the absence of a sinusoidal signal. For individual Fe atoms, we also observe a frequency-dependent response of the state favorability, which can be tuned by the input parameters. In contrast to Fe, there is no significant frequency dependence in the state favorability for individual Co atoms. Based on the Poisson model, the difference in the response of the state favorability can be traced to the difference in the voltage-dependent switching rates of the two different species. This platform provides a tunable way to induce population changes in stochastic systems and provides a foundation toward understanding driven stochastic multiwell systems.
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Affiliation(s)
| | - Hermann Osterhage
- Institute
for Molecules and Materials, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Ruben Christianen
- Institute
for Molecules and Materials, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Kira Junghans
- Institute
for Molecules and Materials, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Eduardo Domínguez
- Donders
Institute for Neuroscience, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Hilbert J. Kappen
- Donders
Institute for Neuroscience, Radboud University, 6525 AJ Nijmegen, The Netherlands
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23
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Stähler C, Reynaerts R, Rinkovec T, Verstraete L, Heideman GH, Minoia A, Harvey JN, Mali KS, De Feyter S, Feringa BL. Highly Ordered Co-Assembly of Bisurea Functionalized Molecular Switches at the Solid-Liquid Interface. Chemistry 2024:e202303994. [PMID: 38323675 DOI: 10.1002/chem.202303994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Indexed: 02/08/2024]
Abstract
Immobilization of stimulus-responsive systems on solid surfaces is beneficial for controlled signal transmission and adaptive behavior while allowing the characterization of the functional interface with high sensitivity and high spatial resolution. Positioning of the stimuli-responsive units with nanometer-scale precision across the adaptive surface remains one of the bottlenecks in the extraction of cooperative function. Nanoscale organization, cooperativity, and amplification remain key challenges in bridging the molecular and the macroscopic worlds. Here we report on the design, synthesis, and scanning tunneling microscopy (STM) characterization of overcrowded alkene photoswitches merged in self-assembled networks physisorbed at the solid-liquid interface. A detailed anchoring strategy that ensures appropriate orientation of the switches with respect to the solid surface through the use of bis-urea groups is presented. We implement a co-assembly strategy that enables the merging of the photoswitches within physisorbed monolayers of structurally similar 'spacer' molecules. The self-assembly of the individual components and the co-assemblies was examined in detail using (sub)molecular resolution STM which confirms the robust immobilization and controlled orientation of the photoswitches within the spacer monolayers. The experimental STM data is supported by detailed molecular mechanics (MM) simulations. Different designs of the switches and the spacers were investigated which allowed us to formulate guidelines that enable the precise organization of the photoswitches in crystalline physisorbed self-assembled molecular networks.
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Affiliation(s)
- Cosima Stähler
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Robby Reynaerts
- Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Tamara Rinkovec
- Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Lander Verstraete
- Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
- imec, Kapeldreef 75, 3001, Leuven, Belgium
| | - G Henrieke Heideman
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Andrea Minoia
- Laboratory for Chemistry of Novel Materials, Materials Research Institute, University of Mons, Place du Parc 20, 7000, Mons, Belgium
| | - Jeremy N Harvey
- Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Kunal S Mali
- Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Steven De Feyter
- Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Ben L Feringa
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
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24
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Li G, Wang H, Loes M, Saxena A, Yin J, Sarker M, Choi S, Aluru N, Lyding JW, Sinitskii A, Dong G. Hybrid Edge Results in Narrowed Band Gap: Bottom-up Liquid-Phase Synthesis of Bent N = 6/8 Armchair Graphene Nanoribbons. ACS Nano 2024; 18:4297-4307. [PMID: 38253346 DOI: 10.1021/acsnano.3c09825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Scalable fabrication of graphene nanoribbons with narrow band gaps has been a nontrivial challenge. Here, we have developed a simple approach to access narrow band gaps using hybrid edge structures. Bottom-up liquid-phase synthesis of bent N = 6/8 armchair graphene nanoribbons (AGNRs) has been achieved in high efficiency through copolymerization between an o-terphenyl monomer and a naphthalene-based monomer, followed by Scholl oxidation. An unexpected 1,2-aryl migration has been discovered, which is responsible for introducing kinked structures into the GNR backbones. The N = 6/8 AGNRs have been fully characterized to support the proposed structure and show a narrow band gap and a relatively high electrical conductivity. In addition, their application in efficient gas sensing has also been demonstrated.
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Affiliation(s)
- Gang Li
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
- Department of Chemistry, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Hanfei Wang
- Department of Electrical and Computer Engineering, Holonyak Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801, United States
| | - Michael Loes
- Department of Chemistry, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Anshul Saxena
- Walker Department of Mechanical Engineering, Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Jiangliang Yin
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Mamun Sarker
- Department of Chemistry, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Shinyoung Choi
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Narayana Aluru
- Walker Department of Mechanical Engineering, Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Joseph W Lyding
- Department of Electrical and Computer Engineering, Holonyak Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801, United States
| | - Alexander Sinitskii
- Department of Chemistry, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Guangbin Dong
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
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25
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Cometto FP, Arisnabarreta N, Vanta R, Jacquelín DK, Vyas V, Lotsch BV, Paredes-Olivera PA, Patrito EM, Lingenfelder M. Rational Design of 2D Supramolecular Networks Switchable by External Electric Fields. ACS Nano 2024; 18:4287-4296. [PMID: 38259041 PMCID: PMC10851663 DOI: 10.1021/acsnano.3c09775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 01/13/2024] [Accepted: 01/17/2024] [Indexed: 01/24/2024]
Abstract
The reversible formation of hydrogen bonds is a ubiquitous mechanism for controlling molecular assembly in biological systems. However, achieving predictable reversibility in artificial two-dimensional (2D) materials remains a significant challenge. Here, we use an external electric field (EEF) at the solid/liquid interface to trigger the switching of H-bond-linked 2D networks using a scanning tunneling microscope. Assisted by density functional theory and molecular dynamics simulations, we systematically vary the molecule-to-molecule interactions, i.e., the hydrogen-bonding strength, as well as the molecule-to-substrate interactions to analyze the EEF switching effect. By tuning the building block's hydrogen-bonding ability (carboxylic acids vs aldehydes) and substrate nature and charge (graphite, graphene/Cu, graphene/SiO2), we induce or freeze the switching properties and control the final polymorphic output in the 2D network. Our results indicate that the switching ability is not inherent to any particular building block but instead relies on a synergistic combination of the relative adsorbate/adsorbate and absorbate/substrate energetic contributions under surface polarization. Furthermore, we describe the dynamics of the switching mechanism based on the rotation of carboxylic groups and proton exchange, which generate the polarizable species that are influenced by the EEF. This work provides insights into the design and control of reversible molecular assembly in 2D materials, with potential applications in a wide range of fields, including sensors and electronics.
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Affiliation(s)
- Fernando P. Cometto
- Max
Planck-EPFL Laboratory for Molecular Nanoscience and IPHYS, EPFL, Lausanne, CH 1015, Switzerland
- Instituto
de Investigaciones en Fisicoquímica de Córdoba (INFIQC),
CONICET, Ciudad Universitaria, Córdoba X5000HUA, Argentina
- Departamento
de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba (UNC), Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - Nicolás Arisnabarreta
- Max
Planck-EPFL Laboratory for Molecular Nanoscience and IPHYS, EPFL, Lausanne, CH 1015, Switzerland
- Instituto
de Investigaciones en Fisicoquímica de Córdoba (INFIQC),
CONICET, Ciudad Universitaria, Córdoba X5000HUA, Argentina
- Departamento
de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba (UNC), Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - Radovan Vanta
- Max
Planck-EPFL Laboratory for Molecular Nanoscience and IPHYS, EPFL, Lausanne, CH 1015, Switzerland
| | - Daniela K. Jacquelín
- Instituto
de Investigaciones en Fisicoquímica de Córdoba (INFIQC),
CONICET, Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - Vijay Vyas
- Max
Planck Institute for Solid State Research, Stuttgart D-70569, Germany
| | - Bettina V. Lotsch
- Max
Planck Institute for Solid State Research, Stuttgart D-70569, Germany
- Department
of Chemistry, University of Munich (LMU), Munich 81377, Germany
| | - Patricia A. Paredes-Olivera
- Departamento
de Química Teórica y Computacional, Facultad de Ciencias
Químicas, Universidad Nacional de
Córdoba (UNC), Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - E. Martín Patrito
- Instituto
de Investigaciones en Fisicoquímica de Córdoba (INFIQC),
CONICET, Ciudad Universitaria, Córdoba X5000HUA, Argentina
- Departamento
de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba (UNC), Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - Magalí Lingenfelder
- Max
Planck-EPFL Laboratory for Molecular Nanoscience and IPHYS, EPFL, Lausanne, CH 1015, Switzerland
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26
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Chesnyak V, Cuxart MG, Baranowski D, Seufert K, Cojocariu I, Jugovac M, Feyer V, Auwärter W. Stripe-Like hBN Monolayer Template for Self-Assembly and Alignment of Pentacene Molecules. Small 2024; 20:e2304803. [PMID: 37821403 DOI: 10.1002/smll.202304803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 09/28/2023] [Indexed: 10/13/2023]
Abstract
Metallic surfaces with unidirectional anisotropy are often used to guide the self-assembly of organic molecules along a particular direction. Such supports thus offer an avenue for the fabrication of hybrid organic-metal interfaces with tailored morphology and precise elemental composition. Nonetheless, such control often comes at the expense of detrimental interfacial interactions that might quench the pristine properties of molecules. Here, hexagonal boron nitride grown on Ir(100) is introduced as a robust platform with several coexisting 1D stripe-like moiré superstructures that effectively guide unidirectional self-assemblies of pentacene molecules, concomitantly preserving their pristine electronic properties. In particular, highly-aligned longitudinal arrays of equally-oriented molecules are formed along two perpendicular directions, as demonstrated by comprehensive scanning tunneling microscopy and photoemission characterization performed at the local and non-local scale, respectively. The functionality of the template is demonstrated by photoemission tomography, a surface-averaging technique requiring a high degree of orientational order of the probed molecules. The successful identification of pentacene's pristine frontier orbitals underlines that the template induces excellent long-range molecular ordering via weak interactions, preventing charge transfer.
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Affiliation(s)
- Valeria Chesnyak
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, 85747, Garching, Germany
- Dipartimento di Fisica, Università degli Studi di Trieste, via A. Valerio 2, Trieste, 34127, Italy
- Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, S.S. 14 km 163.5 in AREA Science Park, Basovizza, Trieste, 34149, Italy
| | - Marc G Cuxart
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, 85747, Garching, Germany
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), 28049, Madrid, Spain
| | - Daniel Baranowski
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich GmbH, 52428, Jülich, Germany
| | - Knud Seufert
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, 85747, Garching, Germany
| | - Iulia Cojocariu
- Dipartimento di Fisica, Università degli Studi di Trieste, via A. Valerio 2, Trieste, 34127, Italy
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich GmbH, 52428, Jülich, Germany
- Elettra-Sincrotrone, S.C.p.A. S.S 14 - km 163.5, Trieste, 34149, Italy
| | - Matteo Jugovac
- Elettra-Sincrotrone, S.C.p.A. S.S 14 - km 163.5, Trieste, 34149, Italy
| | - Vitaliy Feyer
- Peter Grünberg Institute (PGI-6), Forschungszentrum Jülich GmbH, 52428, Jülich, Germany
- Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, 47048, Duisburg, Germany
| | - Willi Auwärter
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, 85747, Garching, Germany
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27
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Voigt J, Hasan M, Wäckerlin C, Karnik AV, Ernst KH. Switching the on-surface orientation of oxygen-functionalized helicene. Chirality 2024; 36:e23642. [PMID: 38384155 DOI: 10.1002/chir.23642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/28/2023] [Accepted: 12/28/2023] [Indexed: 02/23/2024]
Abstract
Helicenes represent an important class of chiral organic material with promising optoelectronic properties. Hence, functionalization of surfaces with helicenes is a key step toward new organic materials devices. The deposition of a heterohelicene containing two furano groups and two hydroxyl groups onto copper(111) surface in ultrahigh vacuum leads to different adsorbate modifications. At low coverage and low temperature, the molecules tend to lie on the surface in order to maximize van der Waals contact with the substrate. Thermal treatment leads to deprotonation of the hydroxyl groups and in part into a reorientation from lying into a standing adsorbate mode.
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Affiliation(s)
- Jan Voigt
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
| | - Mohammed Hasan
- Department of Chemistry, University of Mumbai, Mumbai, India
| | - Christian Wäckerlin
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
- Laboratory for X-ray Nanoscience and Technologies, Paul-Scherrer-Institut (PSI), Villigen, Switzerland
| | - Anil V Karnik
- Department of Chemistry, University of Mumbai, Mumbai, India
| | - Karl-Heinz Ernst
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Department of Chemistry, University of Zurich, Zürich, Switzerland
- Nanosurf Lab, Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
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28
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Meng X, Möller J, Menchón RE, Weismann A, Sánchez-Portal D, Garcia-Lekue A, Herges R, Berndt R. Kondo Effect of Co-Porphyrin: Remarkable Sensitivity to Adsorption Sites and Orientations. Nano Lett 2024; 24:180-186. [PMID: 38150551 DOI: 10.1021/acs.nanolett.3c03669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
We investigated the Kondo effect of cobalt(II)-5-15-bis(4'-bromophenyl)-10,20-bis(4'-iodophenyl)porphyrin (CoTPPBr2I2) molecules on Au(111) with low-temperature scanning tunneling microscopy under ultrahigh vacuum conditions. The molecules exhibit four adsorption configurations at the top and bridge sites of the surface with different molecular orientations. The Kondo resonance shows extraordinary sensitivity to the adsorption configuration. By switching the molecule between different configurations, the Kondo temperature is varied over a wide range from ≈8 up to ≈250 K. Density functional theory calculations reveal that changes of the adsorption configuration lead to distinct variations of the hybridization between the molecule and the surface. Furthermore, we show that surface reconstruction plays a significant role for the molecular Kondo effect.
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Affiliation(s)
- Xiangzhi Meng
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Jenny Möller
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Rodrigo E Menchón
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Facultad de Ciencias Exactas, Ingeniría y Agrimensura (FCEIA), Instituto de Física Rosario (IFIR), 2000 Rosario, Argentina
- Universidad Nacional de Rosario (UNR), 2000 Rosario, Argentina
| | - Alexander Weismann
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Daniel Sánchez-Portal
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Centro de Física de Materiales CSIC-UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - Aran Garcia-Lekue
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Rainer Herges
- Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, 24098 Kiel, Germany
| | - Richard Berndt
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, 24098 Kiel, Germany
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29
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Jiang H, He Y, Lu J, Zheng F, Zhu Z, Yan Y, Sun Q. Unraveling the Mechanisms of On-Surface Photoinduced Reaction with Polarized Light Excitations. ACS Nano 2024; 18:1118-1125. [PMID: 38117979 DOI: 10.1021/acsnano.3c10690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
On-surface reaction has been shown as a powerful strategy to achieve atomically precise nanostructures. Numerous reactions have been realized on surfaces with thermal annealing as the primary excitation. In contrast, far fewer reactions have been triggered by light on surfaces despite its advantages due to the nonthermal process. This is possibly ascribed to our limited understanding on the excitation mechanisms of on-surface photoinduced reactions. In this work, we have studied the photoinduced debrominated coupling by using a linearly polarized light. We successfully achieved the reaction with no annealing process and obtained oligomers as the primary reaction products, which is in contrast with the formation of polymers with traditional thermal treatments. By exploring the dependence of reaction yield on the angle of incidence, we demonstrate an experimental method that can provide fundamental insights. The comparison with the theoretical approximation suggests indirect hot carrier excitation as the leading excitation mechanism. Our results not only provide fundamental insight into the surface photochemical reactions but also set the basis for harnessing light to construct unconventional nanomaterials.
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Affiliation(s)
- Hao Jiang
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Yu He
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Jiayi Lu
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Fengru Zheng
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Zhiwen Zhu
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Yuyi Yan
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Qiang Sun
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
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30
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Li Q, Wang L, Li H, Chan MKY, Hersam MC. Synthesis of Quantum-Confined Borophene Nanoribbons. ACS Nano 2024; 18:483-491. [PMID: 37939213 DOI: 10.1021/acsnano.3c08089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Borophene nanoribbons (BNRs) are one-dimensional strips of atomically thin boron expected to exhibit quantum-confined electronic properties that are not present in extended two-dimensional borophene. While the parent material borophene has been experimentally shown to possess anisotropic metallicity and diverse polymorphic structures, the atomically precise synthesis of nanometer-wide BNRs has not yet been achieved. Here, we demonstrate the synthesis of multiple BNR polymorphs with well-defined edge configurations within the nanometer-scale terraces of vicinal Ag(977). Through atomic-scale imaging, spectroscopy, and first-principles calculations, the synthesized BNR polymorphs are characterized and found to possess distinct edge structures and electronic properties. For single-phase BNRs, v1/6-BNRs and v1/5-BNRs adopt reconstructed armchair edges and sawtooth edges, respectively. In addition, the electronic properties of single-phase v1/6-BNRs and v1/5-BNRs are dominated by Friedel oscillations and striped moiré patterns, respectively. On the other hand, mixed-phase BNRs possess quantum-confined states with increasing nodes in the electronic density of states at elevated biases. Overall, the high degree of polymorphism and diverse edge topologies in borophene nanoribbons provide a rich quantum platform for studying one-dimensional electronic states.
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Affiliation(s)
- Qiucheng Li
- Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
| | - Luqing Wang
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
- Northwestern-Argonne Institute of Science and Engineering, 2205 Tech Drive, Evanston, Illinois 60208, United States
| | - Hui Li
- Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
| | - Maria K Y Chan
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
- Northwestern-Argonne Institute of Science and Engineering, 2205 Tech Drive, Evanston, Illinois 60208, United States
| | - Mark C Hersam
- Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Department of Electrical and Computer Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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31
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Hu T, Minoia A, Velpula G, Ryskulova K, Van Hecke K, Lazzaroni R, Mali KS, Hoogenboom R, De Feyter S. From One-Dimensional Disordered Racemate to Ordered Racemic Conglomerates through Metal-Coordination-Driven Self-Assembly at the Liquid-Solid Interface. Chemistry 2024; 30:e202302545. [PMID: 37840008 DOI: 10.1002/chem.202302545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/17/2023]
Abstract
In recent years, there has been significant focus on investigating and controlling chiral self-assembly, specifically in the context of enantiomeric separation. This study explores the self-assembly behavior of 4-dodecyl-3,6-di(2-pyridyl)pyridazine (DPP-C12) at the interface between heptanoic acid (HA) and highly oriented pyrolytic graphite (HOPG) using a combination of scanning tunneling microscopy (STM) and multiscale molecular modeling. The self-assembled monolayer structure formed by DPP-C12 is periodic in one direction, but aperiodic in the direction orthogonal to it. These structures resemble 1D disordered racemic compounds. Upon introducing palladium [Pd(II)] ions, complexing with DPP-C12, these 1D disordered racemic compounds spontaneously transform into 2D racemic conglomerates, which is rationalized with the assistance of force-field simulations. Our findings provide insights into the regulation of two-dimensional chirality.
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Affiliation(s)
- Tianze Hu
- KU Leuven, Division of Molecular Imaging and Photonics, Department of Chemistry, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Andrea Minoia
- Laboratory for Chemistry of Novel Materials, Materials Research Institute, University of Mons, Place du Parc 20, 7000, Mons, Belgium
| | - Gangamallaiah Velpula
- KU Leuven, Division of Molecular Imaging and Photonics, Department of Chemistry, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Kanykei Ryskulova
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, 9000, Ghent, Belgium
| | - Kristof Van Hecke
- XStruct, Department of Chemistry, Ghent University, Krijgslaan 281 S3, 9000, Ghent, Belgium
| | - Roberto Lazzaroni
- Laboratory for Chemistry of Novel Materials, Materials Research Institute, University of Mons, Place du Parc 20, 7000, Mons, Belgium
| | - Kunal S Mali
- KU Leuven, Division of Molecular Imaging and Photonics, Department of Chemistry, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Richard Hoogenboom
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, 9000, Ghent, Belgium
| | - Steven De Feyter
- KU Leuven, Division of Molecular Imaging and Photonics, Department of Chemistry, Celestijnenlaan 200F, 3001, Leuven, Belgium
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32
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Gao W, Dou W, Zhou D, Song B, Niu T, Hua C, Wee ATS, Zhou M. Epitaxial Growth of 2D Binary Phosphides. Small Methods 2024:e2301512. [PMID: 38175841 DOI: 10.1002/smtd.202301512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Indexed: 01/06/2024]
Abstract
Combinations of phosphorus with main group III, IV, and V elements are theoretically predicted to generate 2D binary phosphides with extraordinary properties and promising applications. However, experimental synthesis is significantly lacking. Here, a general approach for preparing 2D binary phosphides is reported using single crystalline surfaces containing the constituent element of target 2D materials as the substrate. To validate this, SnP3 and BiP, representing typical 2D binary phosphides, are successfully synthesized on Cu2 Sn and bismuthene, respectively. Scanning tunneling microscopy imaging reveals a hexagonal pattern of SnP3 on Cu2 Sn, while α-BiP can be epitaxially grown on the α-bismuthene domain on Cu2 Sb. First-principles calculations reveal that the formation of SnP3 on Cu2 Sn is associated with strong interface bonding and significant charge transfer, while α-BiP interacts weakly with α-bismuthene so that its semiconducting property is preserved. The study demonstrates an attractive avenue for the atomic-scale growth of binary 2D materials via substrate phase engineering.
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Affiliation(s)
- Wenjin Gao
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
- School of Physics, Beihang University, Beijing, 100191, China
| | - Wenzhen Dou
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
- School of Physics, Beihang University, Beijing, 100191, China
| | - Dechun Zhou
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
- Department of Physics, National University of Singapore, Singapore, 117551, Singapore
| | - Biyu Song
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
- School of Physics, Beihang University, Beijing, 100191, China
| | - Tianchao Niu
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
| | - Chenqiang Hua
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
| | - Andrew Thye Shen Wee
- Department of Physics, National University of Singapore, Singapore, 117551, Singapore
| | - Miao Zhou
- Collaborative Center for Physics and Chemistry, Institute of International Innovation, Beihang University, Hangzhou, 311115, China
- School of Physics, Beihang University, Beijing, 100191, China
- Tianmushan Laboratory, Hangzhou, 310023, China
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33
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Parreiras SO, Martín-Fuentes C, Moreno D, Mathialagan SK, Biswas K, Muñiz-Cano B, Lauwaet K, Valvidares M, Valbuena MA, Urgel JI, Gargiani P, Camarero J, Miranda R, Martínez JI, Gallego JM, Écija D. 2D Co-Directed Metal-Organic Networks Featuring Strong Antiferromagnetism and Perpendicular Anisotropy. Small 2023:e2309555. [PMID: 38155502 DOI: 10.1002/smll.202309555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/19/2023] [Indexed: 12/30/2023]
Abstract
Antiferromagnetic spintronics is a rapidly emerging field with the potential to revolutionize the way information is stored and processed. One of the key challenges in this field is the development of novel 2D antiferromagnetic materials. In this paper, the first on-surface synthesis of a Co-directed metal-organic network is reported in which the Co atoms are strongly antiferromagnetically coupled, while featuring a perpendicular magnetic anisotropy. This material is a promising candidate for future antiferromagnetic spintronic devices, as it combines the advantages of 2D and metal-organic chemistry with strong antiferromagnetic order and perpendicular magnetic anisotropy.
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Affiliation(s)
- Sofia O Parreiras
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | - Cristina Martín-Fuentes
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | - Daniel Moreno
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | | | - Kalyan Biswas
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | - Beatriz Muñiz-Cano
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | - Koen Lauwaet
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | | | - Miguel A Valbuena
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
| | - José I Urgel
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
- Unidad de Nanomateriales Avanzados, Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), Unidad Asociada al CSIC por el ICMM, Madrid, 28049, Spain
| | | | - Julio Camarero
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
- Departamento de Física de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Rodolfo Miranda
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
- Departamento de Física de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - José I Martínez
- Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Madrid, 28049, Spain
| | - José M Gallego
- Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Madrid, 28049, Spain
| | - David Écija
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Madrid, 28049, Spain
- Unidad de Nanomateriales Avanzados, Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), Unidad Asociada al CSIC por el ICMM, Madrid, 28049, Spain
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34
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Molino L, Aggarwal L, Maity I, Plumadore R, Lischner J, Luican-Mayer A. Influence of Atomic Relaxations on the Moiré Flat Band Wave Functions in Antiparallel Twisted Bilayer WS 2. Nano Lett 2023; 23:11778-11784. [PMID: 38054731 DOI: 10.1021/acs.nanolett.3c03735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Twisting bilayers of transition metal dichalcogenides gives rise to a moiré potential resulting in flat bands with localized wave functions and enhanced correlation effects. In this work, scanning tunneling microscopy is used to image a WS2 bilayer twisted approximately 3° off the antiparallel alignment. Scanning tunneling spectroscopy reveals localized states in the vicinity of the valence band onset, which is observed to occur first in regions with S-on-S Bernal stacking. In contrast, density functional theory calculations on twisted bilayers that have been relaxed in vacuum predict the highest-lying flat valence band to be localized in regions of AA' stacking. However, agreement with experiment is recovered when the calculations are performed on bilayers in which the atomic displacements from the unrelaxed positions have been reduced, reflecting the influence of the substrate and finite temperature. This demonstrates the delicate interplay of atomic relaxations and the electronic structure of twisted bilayer materials.
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Affiliation(s)
- Laurent Molino
- Department of Physics, University of Ottawa, Ottawa K1N 6X3, Canada
| | - Leena Aggarwal
- Department of Physics, University of Ottawa, Ottawa K1N 6X3, Canada
| | - Indrajit Maity
- Department of Materials, Imperial College London, and Thomas Young Centre for Theory and Simulation of Materials, London SW7 2BP, U.K
| | - Ryan Plumadore
- Department of Physics, University of Ottawa, Ottawa K1N 6X3, Canada
| | - Johannes Lischner
- Department of Materials, Imperial College London, and Thomas Young Centre for Theory and Simulation of Materials, London SW7 2BP, U.K
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35
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Härtl P, Leisegang M, Kügel J, Bode M. Probing Spin-Dependent Ballistic Charge Transport at Single-Nanometer Length Scales. Nano Lett 2023; 23:11608-11613. [PMID: 38096400 PMCID: PMC10755752 DOI: 10.1021/acs.nanolett.3c03404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 12/28/2023]
Abstract
The coherent transport of charge and spin is a key requirement of future devices for quantum computing and communication. Scattering at defects or impurities may significantly reduce the coherence of quantum-mechanical states, thereby affecting the device functionality. While numerous methods exist to experimentally assess charge transport, the real-space detection of a material's ballistic spin transport properties with nanometer resolution remains a challenge. Here we report on a novel approach that utilizes a combination of spin-polarized scanning tunneling microscopy (SP-STM) and the recently introduced molecular nanoprobe (MONA) technique. It relies on the local injection of spin-polarized charge carriers from a magnetic STM tip and their detection by a single surface-deposited phthalocyanine molecule via reversible electron-induced tautomerization events. Based on the particular electronic structure of the Rashba alloy BiAg2, which is governed by a spin-momentum-locked surface state, we prove that the current direction inverses upon tip magnetization reversal.
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Affiliation(s)
- Patrick Härtl
- Physikalisches
Institut, Experimentelle Physik II, Universität
Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Markus Leisegang
- Physikalisches
Institut, Experimentelle Physik II, Universität
Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Jens Kügel
- Physikalisches
Institut, Experimentelle Physik II, Universität
Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Matthias Bode
- Physikalisches
Institut, Experimentelle Physik II, Universität
Würzburg, Am Hubland, 97074 Würzburg, Germany
- Wilhelm
Conrad Röntgen-Center for Complex Material Systems (RCCM), Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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36
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Jacobse P, Daugherty MC, Čerņevičs K, Wang Z, McCurdy RD, Yazyev OV, Fischer FR, Crommie MF. Five-Membered Rings Create Off-Zero Modes in Nanographene. ACS Nano 2023; 17:24901-24909. [PMID: 38051766 PMCID: PMC10753889 DOI: 10.1021/acsnano.3c06006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 11/18/2023] [Accepted: 12/01/2023] [Indexed: 12/07/2023]
Abstract
The low-energy electronic structure of nanographenes can be tuned through zero-energy π-electron states, typically referred to as zero-modes. Customizable electronic and magnetic structures have been engineered by coupling zero-modes through exchange and hybridization interactions. Manipulation of the energy of such states, however, has not yet received significant attention. We find that attaching a five-membered ring to a zigzag edge hosting a zero-mode perturbs the energy of that mode and turns it into an off-zero mode: a localized state with a distinctive electron-accepting character. Whereas the end states of typical 7-atom-wide armchair graphene nanoribbons (7-AGNRs) lose their electrons when physisorbed on Au(111) (due to its high work function), converting them into off-zero modes by introducing cyclopentadienyl five-membered rings allows them to retain their single-electron occupation. This approach enables the magnetic properties of 7-AGNR end states to be explored using scanning tunneling microscopy (STM) on a gold substrate. We find a gradual decrease of the magnetic coupling between off-zero mode end states as a function of GNR length, and evolution from a more closed-shell to a more open-shell ground state.
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Affiliation(s)
- Peter
H. Jacobse
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Michael C. Daugherty
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kristia̅ns Čerņevičs
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ziyi Wang
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Ryan D. McCurdy
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Oleg V. Yazyev
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Felix R. Fischer
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Bakar
Institute
of Digital Materials for the Planet, Division of Computing, Data Science,
and Society, University of California, Berkeley, California 94720, United States
| | - Michael F. Crommie
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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37
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Xu K, Holbrook M, Holtzman LN, Pasupathy AN, Barmak K, Hone JC, Rosenberger MR. Validating the Use of Conductive Atomic Force Microscopy for Defect Quantification in 2D Materials. ACS Nano 2023; 17:24743-24752. [PMID: 38095969 DOI: 10.1021/acsnano.3c05056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Defects significantly affect the electronic, chemical, mechanical, and optical properties of two-dimensional (2D) materials. Thus, it is critical to develop a method for convenient and reliable defect quantification. Scanning transmission electron microscopy (STEM) and scanning tunneling microscopy (STM) possess the required atomic resolution but have practical disadvantages. Here, we benchmark conductive atomic force microscopy (CAFM) by a direct comparison with STM in the characterization of transition metal dichalcogenides (TMDs). The results conclusively demonstrate that CAFM and STM image identical defects, giving results that are equivalent both qualitatively (defect appearance) and quantitatively (defect density). Further, we confirm that CAFM can achieve single-atom resolution, similar to that of STM, on both bulk and monolayer samples. The validation of CAFM as a facile and accurate tool for defect quantification provides a routine and reliable measurement that can complement other standard characterization techniques.
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Affiliation(s)
- Kaikui Xu
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Madisen Holbrook
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Luke N Holtzman
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - Abhay N Pasupathy
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Katayun Barmak
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - James C Hone
- Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States
| | - Matthew R Rosenberger
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
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38
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Dong W, Li X, Lu S, Li J, Wang Y, Zhong M, Dong X, Xu Z, Shen Q, Gao S, Wu K, Peng LM, Hou S, Zhang Z, Zhang Y, Wang Y. Unzipping Carbon Nanotubes to Sub-5-nm Graphene Nanoribbons on Cu(111) by Surface Catalysis. Small 2023:e2308430. [PMID: 38126626 DOI: 10.1002/smll.202308430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/23/2023] [Indexed: 12/23/2023]
Abstract
Graphene nanoribbons (GNRs) are promising in nanoelectronics for their quasi-1D structures with tunable bandgaps. The methods for controllable fabrication of high-quality GNRs are still limited. Here a way to generate sub-5-nm GNRs by annealing single-walled carbon nanotubes (SWCNTs) on Cu(111) is demonstrated. The structural evolution process is characterized by low-temperature scanning tunneling microscopy. Substrate-dependent measurements on Au(111) and Ru(0001) reveal that the intermediate strong SWCNT-surface interaction plays a pivotal role in the formation of GNRs.
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Affiliation(s)
- Wenjie Dong
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Xin Li
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Shuai Lu
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Jie Li
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Yansong Wang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Mingjun Zhong
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Xu Dong
- Institute of Spin Science and Technology, South China University of Technology, Guangzhou, 511442, China
| | - Zhen Xu
- Institute of Spin Science and Technology, South China University of Technology, Guangzhou, 511442, China
| | - Qian Shen
- Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Nanjing Tech University, Nanjing, 211816, China
| | - Song Gao
- Institute of Spin Science and Technology, South China University of Technology, Guangzhou, 511442, China
| | - Kai Wu
- BNLMS, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Lian-Mao Peng
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Shimin Hou
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Zhiyong Zhang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Yajie Zhang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Yongfeng Wang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
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39
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Cortés-Del Río E, Trivini S, Pascual JI, Cherkez V, Mallet P, Veuillen JY, Cuevas JC, Brihuega I. Shaping Graphene Superconductivity with Nanometer Precision. Small 2023:e2308439. [PMID: 38112230 DOI: 10.1002/smll.202308439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/23/2023] [Indexed: 12/21/2023]
Abstract
Graphene holds great potential for superconductivity due to its pure 2D nature, the ability to tune its carrier density through electrostatic gating, and its unique, relativistic-like electronic properties. At present, still far from controlling and understanding graphene superconductivity, mainly because the selective introduction of superconducting properties to graphene is experimentally very challenging. Here, a method is developed that enables shaping at will graphene superconductivity through a precise control of graphene-superconductor junctions. The method combines the proximity effect with scanning tunnelling microscope (STM) manipulation capabilities. Pb nano-islands are first grown that locally induce superconductivity in graphene. Using a STM, Pb nano-islands can be selectively displaced, over different types of graphene surfaces, with nanometre scale precision, in any direction, over distances of hundreds of nanometres. This opens an exciting playground where a large number of predefined graphene-superconductor hybrid structures can be investigated with atomic scale precision. To illustrate the potential, a series of experiments are performed, rationalized by the quasi-classical theory of superconductivity, going from the fundamental understanding of superconductor-graphene-superconductor heterostructures to the construction of superconductor nanocorrals, further used as "portable" experimental probes of local magnetic moments in graphene.
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Affiliation(s)
- Eva Cortés-Del Río
- Departamento Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, E-28049, Spain
| | | | - José I Pascual
- CIC nanoGUNE-BRTA, Donostia-San Sebastián, 20018, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, 48013, Spain
| | - Vladimir Cherkez
- Université Grenoble Alpes, CNRS, Institut Néel, Grenoble, F-38400, France
- CNRS, Institut Neel, Grenoble, F-38042, France
| | - Pierre Mallet
- Université Grenoble Alpes, CNRS, Institut Néel, Grenoble, F-38400, France
- CNRS, Institut Neel, Grenoble, F-38042, France
| | - Jean-Yves Veuillen
- Université Grenoble Alpes, CNRS, Institut Néel, Grenoble, F-38400, France
- CNRS, Institut Neel, Grenoble, F-38042, France
| | - Juan C Cuevas
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, E-28049, Spain
- Departamento Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
- Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
| | - Iván Brihuega
- Departamento Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, E-28049, Spain
- Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
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40
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Peng X, Zhang Y, Liu X, Qian Y, Ouyang Z, Kong H. From Short- to Long-Range Chiral Recognition on Surfaces: Chiral Assembly and Synthesis. Small 2023:e2307171. [PMID: 38054810 DOI: 10.1002/smll.202307171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 11/13/2023] [Indexed: 12/07/2023]
Abstract
Research on chiral behaviors of small organic molecules at solid surfaces, including chiral assembly and synthesis, can not only help unravel the origin of the chiral phenomenon in biological/chemical systems but also provide promising strategies to build up unprecedented chiral surfaces or nanoarchitectures with advanced applications in novel nanomaterials/nanodevices. Understanding how molecular chirality is recognized is considered to be a mandatory basis for such studies. In this review, a series of recent studies in chiral assembly and synthesis at well-defined metal surfaces under ultra-high vacuum conditions are outlined. More importantly, the intrinsic mechanisms of chiral recognition are highlighted, including short/long-range chiral recognition in chiral assembly and two main strategies to steer the reaction pathways and modulate selective synthesis of specific chiral products on surfaces.
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Affiliation(s)
- Xinchen Peng
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Yinhui Zhang
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Xinbang Liu
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Yinyue Qian
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Zuoling Ouyang
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Huihui Kong
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
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41
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Sun K, Sugawara K, Lyalin A, Ishigaki Y, Uosaki K, Custance O, Taketsugu T, Suzuki T, Kawai S. On-Surface Synthesis of Multiple Cu Atom-Bridged Organometallic Oligomers. ACS Nano 2023. [PMID: 38047624 DOI: 10.1021/acsnano.3c10524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
A metal-metal bond between coordination complexes has the nature of a covalent bond in hydrocarbons. While bimetallic and trimetallic compounds usually have three-dimensional structures in solution, the high directionality and robustness of the bond can be applied for on-surface syntheses. Here, we present a systematic formation of complex organometallic oligomers on Cu(111) through sequential ring opening of 11,11,12,12-tetraphenyl-1,4,5,8-tetraazaanthraquinodimethane and bonding of phenanthroline derivatives by multiple Cu atoms. A detailed characterization with a combination of scanning tunneling microscopy and density functional theory calculations revealed the role of the Cu adatoms in both enantiomers of the chiral oligomers. Furthermore, we found sufficient strength of the bonds against sliding friction by manipulating the oligomers up to a hexamer. This finding may help to increase the variety of organometallic nanostructures on surfaces.
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Affiliation(s)
- Kewei Sun
- Center for Basic Research on Materials, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
- International Center for Young Scientists, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
| | - Kazuma Sugawara
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Andrey Lyalin
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD) Hokkaido University, Sapporo 001-0021, Japan
- Global Research Center for Environment and Energy based on Nanomaterials Science, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Yusuke Ishigaki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Kohei Uosaki
- Global Research Center for Environment and Energy based on Nanomaterials Science, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Oscar Custance
- Center for Basic Research on Materials, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Tetsuya Taketsugu
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD) Hokkaido University, Sapporo 001-0021, Japan
| | - Takanori Suzuki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Shigeki Kawai
- Center for Basic Research on Materials, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571, Japan
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Saruta Y, Sugawara K, Oka H, Kawakami T, Kato T, Nakayama K, Souma S, Takahashi T, Fukumura T, Sato T. Moiré-Assisted Realization of Octahedral MoTe 2 Monolayer. Adv Sci (Weinh) 2023; 10:e2304461. [PMID: 37867224 DOI: 10.1002/advs.202304461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/24/2023] [Indexed: 10/24/2023]
Abstract
A current key challenge in 2D materials is the realization of emergent quantum phenomena in hetero structures via controlling the moiré potential created by the periodicity mismatch between adjacent layers, as highlighted by the discovery of superconductivity in twisted bilayer graphene. Generally, the lattice structure of the original host material remains unchanged even after the moiré superlattice is formed. However, much less attention is paid for the possibility that the moiré potential can also modify the original crystal structure itself. Here, it is demonstrated that octahedral MoTe2 which is unstable in bulk is stabilized in a commensurate MoTe2 /graphene hetero-bilayer due to the moiré potential created between the two layers. It is found that the reconstruction of electronic states via the moiré potential is responsible for this stabilization, as evidenced by the energy-gap opening at the Fermi level observed by angle-resolved photoemission and scanning tunneling spectroscopies. The present results provide a fresh approach to realize novel 2D quantum phases by utilizing the moiré potential.
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Affiliation(s)
- Yasuaki Saruta
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
| | - Katsuaki Sugawara
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, 980-8577, Japan
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Tokyo, 102-0076, Japan
| | - Hirofumi Oka
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, 980-8577, Japan
| | - Tappei Kawakami
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
| | - Takemi Kato
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
| | - Kosuke Nakayama
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Tokyo, 102-0076, Japan
| | - Seigo Souma
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, 980-8577, Japan
- Center for Science and Innovation in Spintronics (CSIS), Tohoku University, Sendai, 980-8577, Japan
| | - Takashi Takahashi
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
| | - Tomoteru Fukumura
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
| | - Takafumi Sato
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, 980-8577, Japan
- Center for Science and Innovation in Spintronics (CSIS), Tohoku University, Sendai, 980-8577, Japan
- International Center for Synchrotron Radiation Innovation Smart (SRIS), Tohoku University, Sendai, 980-8577, Japan
- Mathematical Science Center for Co-creative Society (MathCCS), Tohoku University, Sendai, 980-8578, Japan
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43
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Song X, Huang X, Yang H, Jia L, Zhang Q, Huang Y, Wu X, Liu L, Gao HJ, Wang Y. Robust Behavior of Charge Density Wave Quantum Motif Star-of-David in 2D NbSe 2 Nanocrystals. Small 2023; 19:e2305159. [PMID: 37635109 DOI: 10.1002/smll.202305159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/02/2023] [Indexed: 08/29/2023]
Abstract
Charge density wave (CDW) is a typical collective phenomenon, and the phase change is generally accompanied by electronic transition with potential device applications. For the continuous miniaturization of devices, it is important to investigate the size effect down to the nanoscale. In this work, single-layer (SL) 1T-NbSe2 islands provide an ideal research platform to investigate the size effect on CDW arrangement and electronic states. The CDW motifs (Star-of-David [SOD]) at the island border are along the edge, and those at the interior tend to arrange in a triangular lattice for islands as small as 5 nm. Interestingly, in some small islands, the SOD clusters rearrange into a square-like lattice, and each SOD cluster remains robust as a quantum motif, both in the sense of geometry and electronic structures. Moreover, the electronic structure at the center of the small islands is downwards shifted compared to the big islands, explained by the spatial extension of the band bending originating from the edge of the islands. These findings reveal the robust behavior of CDW motifs down to the nanoscale and provide new insights into the size-limiting effect on 2D2D CDW ordering and electronic states down to a few nanometer extremes.
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Affiliation(s)
- Xuan Song
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Xinyu Huang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Han Yang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Liangguang Jia
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Quanzhen Zhang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Yuan Huang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Xu Wu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Liwei Liu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
| | - Hong-Jun Gao
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yeliang Wang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, China
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44
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Chen Y, Zhang Y, Wang W, Song X, Jia LG, Zhang C, Zhou L, Han X, Yang HX, Liu LW, Si C, Gao HJ, Wang YL. Visualization of Confined Electrons at Grain Boundaries in a Monolayer Charge-Density-Wave Metal. Adv Sci (Weinh) 2023:e2306171. [PMID: 37984874 DOI: 10.1002/advs.202306171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/11/2023] [Indexed: 11/22/2023]
Abstract
1D grain boundaries in transition metal dichalcogenides (TMDs) are ideal for investigating the collective electron behavior in confined systems. However, clear identification of atomic structures at the grain boundaries, as well as precise characterization of the electronic ground states, have largely been elusive. Here, direct evidence for the confined electronic states and the charge density modulations at mirror twin boundaries (MTBs) of monolayer NbSe2 , a representative charge-density-wave (CDW) metal, is provided. The scanning tunneling microscopy (STM) measurements, accompanied by the first-principles calculations, reveal that there are two types of MTBs in monolayer NbSe2 , both of which exhibit band bending effect and 1D boundary states. Moreover, the intrinsic CDW signatures of monolayer NbSe2 are dramatically suppressed as approaching an isolated MTB but can be either enhanced or suppressed in the MTB-constituted confined wedges. Such a phenomenon can be well explained by the MTB-CDW interference interactions. The results reveal the underlying physics of the confined electrons at MTBs of CDW metals, paving the way for the grain boundary engineering of the functionality.
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Affiliation(s)
- Yaoyao Chen
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Yu Zhang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
- Advanced Research Institute of Multidisciplinary Sciences, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Wei Wang
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, P. R. China
| | - Xuan Song
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Liang-Guang Jia
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Can Zhang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Lili Zhou
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Xu Han
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Hui-Xia Yang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Li-Wei Liu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Chen Si
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, P. R. China
| | - Hong-Jun Gao
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Ye-Liang Wang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing, 100081, P. R. China
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45
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Pushkarna I, Pásztor Á, Renner C. Twist-Angle-Dependent Electronic Properties of Exfoliated Single Layer MoS 2 on Au(111). Nano Lett 2023; 23:9406-9412. [PMID: 37844067 PMCID: PMC10603799 DOI: 10.1021/acs.nanolett.3c02804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/29/2023] [Indexed: 10/18/2023]
Abstract
Synthetic materials and heterostructures obtained by the controlled stacking of exfoliated monolayers are emerging as attractive functional materials owing to their highly tunable properties. We present a detailed scanning tunneling microscopy and spectroscopy study of single layer MoS2-on-gold heterostructures as a function of the twist angle. We find that their electronic properties are determined by the hybridization of the constituent layers and are modulated at the moiré period. The hybridization depends on the layer alignment, and the modulation amplitude vanishes with increasing twist angle. We explain our observations in terms of a hybridization between the nearest sulfur and gold atoms, which becomes spatially more homogeneous and weaker as the moiré periodicity decreases with increasing twist angle, unveiling the possibility of tunable hybridization of electronic states via twist angle engineering.
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Affiliation(s)
| | | | - Christoph Renner
- Department of Quantum Matter
Physics, Université de Genève, 24 Quai Ernest Ansermet, CH-1211 Geneva, Switzerland
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46
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Lu J, Nieckarz D, Jiang H, Zhu Z, Yan Y, Zheng F, Rżysko W, Lisiecki J, Szabelski P, Sun Q. Order-Disorder Transition of Two-Dimensional Molecular Networks through a Stoichiometric Design. ACS Nano 2023; 17:20194-20202. [PMID: 37788293 DOI: 10.1021/acsnano.3c05945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Materials with disordered structures may exhibit interesting properties. Metal-organic frameworks (MOFs) are a class of hybrid materials composed of metal nodes and coordinating organic linkers. Recently, there has been growing interest in MOFs with structural disorder and the investigations of amorphous structures on surfaces. Herein, we demonstrate a bottom-up method to construct disordered molecular networks on metal surfaces by selecting two organic molecule linkers with the same symmetry but different sizes for preparing two-component samples with different stoichiometric ratios. The amorphous networks are directly imaged by scanning tunneling microscopy under ultrahigh vacuum with a submolecular resolution, allowing us to quantify its degree of disorder and other structural properties. Furthermore, we resort to molecular dynamics simulations to understand the formation of the amorphous metal-organic networks. The results may advance our understanding of the mechanism of formation of monolayer molecular networks with structural disorders, facilitating the design and exploration of amorphous MOF materials with intriguing properties.
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Affiliation(s)
- Jiayi Lu
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Damian Nieckarz
- Department of Theoretical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin, 20-031 Lublin, Poland
| | - Hao Jiang
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Zhiwen Zhu
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Yuyi Yan
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Fengru Zheng
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
| | - Wojciech Rżysko
- Department of Theoretical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin, 20-031 Lublin, Poland
| | - Jakub Lisiecki
- Department of Theoretical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin, 20-031 Lublin, Poland
| | - Paweł Szabelski
- Department of Theoretical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University in Lublin, 20-031 Lublin, Poland
| | - Qiang Sun
- Materials Genome Institute, Shanghai University, 200444 Shanghai, China
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47
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Nhung Nguyen TT, Power SR, Karakachian H, Starke U, Tegenkamp C. Quantum Confinement in Epitaxial Armchair Graphene Nanoribbons on SiC Sidewalls. ACS Nano 2023; 17:20345-20352. [PMID: 37788294 DOI: 10.1021/acsnano.3c06449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The integration of graphene into devices necessitates large-scale growth and precise nanostructuring. Epitaxial growth of graphene on SiC surfaces offers a solution by enabling both simultaneous and targeted realization of quantum structures. We investigated the impact of local variations in the width and edge termination of armchair graphene nanoribbons (AGNRs) on quantum confinement effects using scanning tunneling microscopy and spectroscopy (STM, STS), along with density-functional tight-binding (DFTB) calculations. AGNRs were grown as an ensemble on refaceted sidewalls of SiC mesas with adjacent AGNRs separated by SiC(0001) terraces hosting a buffer layer seamlessly connected to the AGNRs. Energy band gaps measured by STS at the centers of ribbons of different widths align with theoretical expectations, indicating that hybridization of π-electrons with the SiC substrate mimics sharp electronic edges. However, regardless of the ribbon width, band gaps near the edges of AGNRs are significantly reduced. DFTB calculations successfully replicate this effect by considering the role of edge passivation, while strain or electric fields do not account for the observed effect. Unlike idealized nanoribbons with uniform hydrogen passivation, AGNRs on SiC sidewalls generate additional energy bands with non-pz character and nonuniform distribution across the nanoribbon. In AGNRs terminated with Si, these additional states occur at the conduction band edge and rapidly decay into the bulk of the ribbon. This agrees with our experimental findings, demonstrating that edge passivation is crucial in determining the local electronic properties of epitaxial nanoribbons.
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Affiliation(s)
- Thi Thuy Nhung Nguyen
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany
| | - Stephen R Power
- School of Physical Sciences, Dublin City University, Glasnevin, 9 Dublin, Ireland
| | - Hrag Karakachian
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Ulrich Starke
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Christoph Tegenkamp
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany
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48
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Li Z, Li Y, Yin C. Manipulating Molecular Self-Assembly Process at the Solid-Liquid Interface Probed by Scanning Tunneling Microscopy. Polymers (Basel) 2023; 15:4176. [PMID: 37896420 PMCID: PMC10610993 DOI: 10.3390/polym15204176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
The phenomenon of ordered self-assembly on solid substrates is a topic of interest in both fundamental surface science research and its applications in nanotechnology. The regulation and control of two-dimensional (2D) self-assembled supra-molecular structures on surfaces have been realized through applying external stimuli. By utilizing scanning tunneling microscopy (STM), researchers can investigate the detailed phase transition process of self-assembled monolayers (SAMs), providing insight into the interplay between intermolecular weak interactions and substrate-molecule interactions, which govern the formation of molecular self-assembly. This review will discuss the structural transition of self-assembly probed by STM in response to external stimuli and provide state-of-the-art methods such as tip-induced confinement for the alignment of SAM domains and selective chirality. Finally, we discuss the challenges and opportunities in the field of self-assembly and STM.
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Affiliation(s)
| | - Yanan Li
- School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001, China;
| | - Chengjie Yin
- School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001, China;
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Li Y, Zhai S, Liu Y, Zhang J, Meng Z, Zhuang J, Feng H, Xu X, Hao W, Zhou M, Lu GH, Dou SX, Du Y. Electronic Flat Band in Distorted Colouring Triangle Lattice. Adv Sci (Weinh) 2023:e2303483. [PMID: 37840399 DOI: 10.1002/advs.202303483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/19/2023] [Indexed: 10/17/2023]
Abstract
Dispersionless flat bands (FBs) in momentum space, given rise to electron destructive interference in frustrated lattices, offer opportunities to enhance electronic correlations and host exotic many-body phenomena, such as Wigner crystal, fractional quantum hall state, and superconductivity. Despite successes in theory, great challenges remain in experimentally realizing FBs in frustrated lattices due to thermodynamically structural instability. Here, the observation of electronic FB in a potassium distorted colouring triangle (DCT) lattice is reported, which is supported on a blue phosphorene-gold network. It is verified that the interaction between potassium and the underlayer dominates and stabilizes the frustrated structures. Two-dimensional electron gas is modulated by the DCT lattice, and in turn results in a FB dispersion due to destructive quantum interferences. The FB exhibits suppressed bandwidth with high density of states, which is directly observed by scanning tunneling microscopy and confirmed by the first-principles calculation. This work demonstrates that DCT lattice is a promising platform to study FB physics and explore exotic phenomena of correlation and topological matters.
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Affiliation(s)
- Yaqi Li
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
| | - Shuwei Zhai
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
| | - Yani Liu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jingwei Zhang
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
| | - Ziyuan Meng
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
| | - Jincheng Zhuang
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
| | - Haifeng Feng
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
| | - Xun Xu
- Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong, Wollongong, New South Wales, 2500, Australia
| | - Weichang Hao
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
| | - Miao Zhou
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Beihang Hangzhou Innovation Institute Yuhang, Hangzhou, 310023, China
| | - Guang-Hong Lu
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing, 100191, China
| | - Shi Xue Dou
- Institute of Energy Materials Science, University of Shanghai for Science and Technology, Yangpu, Shanghai, 200093, China
| | - Yi Du
- School of Physics, Beihang University, Haidian, Beijing, 100191, China
- Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing, 100191, China
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Tenorio M, Moreno C, Vilas-Varela M, Castro-Esteban J, Febrer P, Pruneda M, Peña D, Mugarza A. Introducing Design Strategies to Preserve N-Heterocycles Throughout the On-Surface Synthesis of Graphene Nanostructures. Small Methods 2023:e2300768. [PMID: 37840449 DOI: 10.1002/smtd.202300768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Indexed: 10/17/2023]
Abstract
Despite the impressive advances in the synthesis of atomically precise graphene nanostructures witnessed during the last decade, advancing in compositional complexity faces major challenges. The concept of introducing the desired functional groups or dopants in the molecular precursor often fails due to their lack of stability during the reaction path. Here, a study on the stability of different pyridine and pyrimidine moieties during the on-surface synthesis of graphene nanoribbons on Au(111) is presented. Combining bond-resolved scanning tunneling microscopy with X-ray photoelectron spectroscopy, the thermal evolution of the nitrogen dopants throughout the whole reaction sequence is tracked. A comparative experimental and ab initio electronic characterization confirms the presence of dopants in the final structures, revealing also that the pyridinic nitrogen leads to a significant band downshift. The results demonstrate that, by using synthetic strategies to lower the reaction temperatures, one can preserve specific N-heterocycles throughout all the reaction steps of the synthesis of graphene nanoribbons and beyond the interibbon coupling reaction that leads to nanoporous graphene.
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Affiliation(s)
- Maria Tenorio
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Bellaterra, Barcelona, 08193, Spain
| | - Cesar Moreno
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Bellaterra, Barcelona, 08193, Spain
- Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Santander, 39005, Spain
| | - Manuel Vilas-Varela
- Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Santiago de Compostela, 15782, Spain
| | - Jesús Castro-Esteban
- Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Santiago de Compostela, 15782, Spain
| | - Pol Febrer
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Bellaterra, Barcelona, 08193, Spain
| | - Miguel Pruneda
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Bellaterra, Barcelona, 08193, Spain
| | - Diego Peña
- Centro de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Santiago de Compostela, 15782, Spain
| | - Aitor Mugarza
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Bellaterra, Barcelona, 08193, Spain
- ICREA Institució Catalana de Recerca i Estudis Avançats, Barcelona, 08010, Spain
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