1
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Chen Z, Wang S, Xiong W, Wang F. Enhancing the energetic and magnetic stability of atomic hydrogen chemisorbed on graphene using (non)compensated B-N pairs. Phys Chem Chem Phys 2024; 26:13731-13739. [PMID: 38682161 DOI: 10.1039/d4cp00923a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
In this pioneering study for identifying atomic scale magnetic moment, a single hydrogen atom chemisorbed on pristine graphene exhibits distinct spin polarization. Using first-principles calculations and analyses, we demonstrate that the binding between a H adsorbate and a C substrate is substantially enhanced via compensated B-N pairs embedded into graphene. Surprisingly, the interaction can be further enhanced via non-compensated B-N pair doping. Our established prototype of orbital intercoupling between H 1s and hybridized pz of gapped band edges gives an insight into the enhancing mechanism. For compensated B-N doping, the conduction band minimum (CBM) is pushed upward, which induces stronger interaction between the H 1s and hybridized pz orbitals of the CBM. For non-compensated B-N doping, the orbital interaction occurs between H 1s and hybridized pz orbitals of valence band maximum, thus further lowering the resulting bonding energy due to the enlarged gap. This significantly enhanced interaction between H and C atoms agrees well with the results of charge localization at the gapped band edges. More importantly, the corresponding magnetic moments can be well maintained or even enhanced in both doping; here, one more H atom is needed for non-compensated doping, where its electron occupies the empty CBM. Our findings might provide an effective and practical way to enhance the energetic and magnetic stability of atomic scale magnetic moment on graphene and extensively expand the conception of non-compensated doping.
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Affiliation(s)
- Zhengyan Chen
- College of Software, Henan Finance University, Zhengzhou 450046, China
| | - Sanjun Wang
- College of Artificial Intelligence, Henan Finance University, Zhengzhou 450046, China
| | - Wen Xiong
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Fei Wang
- International Laboratory for Quantum Functional Materials of Henan, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, China.
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2
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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 (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2308430. [PMID: 38126626 DOI: 10.1002/smll.202308430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [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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3
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Zhang Q, Cai L, Liao N, Lu Y, Zhang J, Zhang C, Zeng K. Work Function Prediction by Graph Neural Networks for Configurationally Hybridized Boron-Doped Graphene. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7087-7094. [PMID: 38511875 DOI: 10.1021/acs.langmuir.4c00228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
Graphene, serving as electrodes, is widely applied in electronic and optoelectronic devices. Work function as one of the fundamental intrinsic characteristics of graphene directly affects the interfacial properties of the electrodes, thereby affecting the performance of the devices. Much work has been done to regulate the work function of graphene to expand its application fields, and doping has been demonstrated as an effective method. However, the numerous types of doped graphene make the investigation of its work function time-consuming and labor-intensive. In order to quickly obtain the relationship between the structure and property, a deep learning method is employed to predict the work function in this study. Specifically, a data set of over 30,000 compositions with the work function on boron-doped graphene at different concentrations and doping positions via density functional theory simulations was established through ab initio calculations. Then, a novel fusion model (GT-Net) combining transformers and graph neural networks (GNNs) was proposed. After that, improved effective GNN-based descriptors were developed. Finally, three different GNN methods were compared, and the results show that the proposed method could accurately predicate the work function with the R2 = 0.975 and RMSE = 0.027. This study not only provides the possibility of designing materials with specific properties at the atomic level but also demonstrates the performance of GNNs on graph-level tasks with the same graph structure and atomic number.
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Affiliation(s)
- Qingwei Zhang
- Chongqing University of Technology, Chongqing 401120, China
| | - Lin Cai
- Chongqing University of Technology, Chongqing 401120, China
| | - Ningsheng Liao
- Chongqing University of Technology, Chongqing 401120, China
| | - Yunhua Lu
- Chongqing University of Technology, Chongqing 401120, China
| | - Junan Zhang
- Chongqing University of Technology, Chongqing 401120, China
| | - Chao Zhang
- School of Chemical Engineering, Qinghai University, Xining 810016, China
| | - Kangli Zeng
- Chongqing University of Technology, Chongqing 401120, China
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4
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Li C, Wang F, Cui B, Pan Z, Jia Y. Localized magnetic moment induced by boron adatoms chemisorbed on graphene. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35. [PMID: 37068487 DOI: 10.1088/1361-648x/accdad] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 04/17/2023] [Indexed: 05/16/2023]
Abstract
Inducing local spin-polarization in pristine graphene is highly desirable and recent experiment shows that boron adatom chemical attachment to graphene exhibits local high spin state. Using hybrid exchange-correlation functional, we show that boron (B) monomer chemisorbed on the bridge site of graphene is energically favorable, and indeed induces a weak local spin-polarization ∼0.56μB. The localized magnetic moment can be attributed to the charge transfer from boron atom to graphene, resulting in local spin charge dominantly surrounding to the adsorbed B and neighboring carbon (C) atoms. We also surprisingly find that boron dimer can even much more stable upright anchor the same site of graphene, giving rise to sizable spin magnetic moment 2.00μB. Although the apparent spin state remains mainly contributed by Bpand Cporbitals as the case of boron monomer, the delicate and substantial charge transfer of theintra-dimerplays a fundamental role in producing such sizable local spin-polarization. We employed various van der Waals corrections to check and confirm the validity of appeared local spin-polarization. In terms of the almost identical simulated scanning tunneling microscope between boron monomer and dimer, we might tend to support the fact that boron dimer can also be chemisorbed on graphene with much larger and stable localized spin magnetic moment.
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Affiliation(s)
- Chong Li
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, People's Republic of China
| | - Fei Wang
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, People's Republic of China
| | - Bin Cui
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, People's Republic of China
| | - Zhifeng Pan
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, People's Republic of China
| | - Yu Jia
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, People's Republic of China
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5
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Gao F, Li D, Barreteau C, Brandbyge M. Proposal for All-Electrical Spin Manipulation and Detection for a Single Molecule on Boron-Substituted Graphene. PHYSICAL REVIEW LETTERS 2022; 129:027201. [PMID: 35867446 DOI: 10.1103/physrevlett.129.027201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/08/2022] [Accepted: 06/03/2022] [Indexed: 06/15/2023]
Abstract
All-electrical writing and reading of spin states attract considerable attention for their promising applications in energy-efficient spintronics devices. Here we show, based on rigorous first-principles calculations, that the spin properties can be manipulated and detected in molecular spinterfaces, where an iron tetraphenyl porphyrin (FeTPP) molecule is deposited on boron-substituted graphene (BG). Notably, a reversible spin switching between the S=1 and S=3/2 states is achieved by a gate electrode. We can trace the origin to a strong hybridization between the Fe-d_{z^{2}} and B-p_{z} orbitals. Combining density functional theory with nonequilibrium Green's function formalism, we propose an experimentally feasible three-terminal setup to probe the spin state. Furthermore, we show how the in-plane quantum transport for the BG, which is non-spin polarized, can be modified by FeTPP, yielding a significant transport spin polarization near the Fermi energy (>10% for typical coverage). Our work paves the way to realize all-electrical spintronics devices using molecular spinterfaces.
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Affiliation(s)
- Fei Gao
- Department of Physics, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Dongzhe Li
- CEMES, Université de Toulouse, CNRS, 29 rue Jeanne Marvig, F-31055 Toulouse, France
| | - Cyrille Barreteau
- Université Paris-Saclay, CEA, CNRS, SPEC, 91191 Gif-sur-Yvette, France
| | - Mads Brandbyge
- Department of Physics, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
- Center for Nanostructured Graphene, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
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6
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Voroshnin V, Tarasov AV, Bokai KA, Chikina A, Senkovskiy BV, Ehlen N, Usachov DY, Grüneis A, Krivenkov M, Sánchez-Barriga J, Fedorov A. Direct Spectroscopic Evidence of Magnetic Proximity Effect in MoS 2 Monolayer on Graphene/Co. ACS NANO 2022; 16:7448-7456. [PMID: 35442015 DOI: 10.1021/acsnano.1c10391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A magnetic field modifies optical properties and provides valley splitting in a molybdenum disulfide (MoS2) monolayer. Here we demonstrate a scalable approach to the epitaxial synthesis of MoS2 monolayer on a magnetic graphene/Co system. Using spin- and angle-resolved photoemission spectroscopy we observe a magnetic proximity effect that causes a 20 meV spin-splitting at the Γ̅ point and canting of spins at the K̅ point in the valence band toward the in-plane direction of cobalt magnetization. Our density functional theory calculations reveal that the in-plane spin component at K̅ is localized on Co atoms in the valence band, while in the conduction band it is localized on the MoS2 layer. The calculations also predict a 16 meV spin-splitting at the Γ̅ point and 8 meV K̅-K'¯ valley asymmetry for an out-of-plane magnetization. These findings suggest control over optical transitions in MoS2 via Co magnetization. Our estimations show that the magnetic proximity effect is equivalent to the action of the magnetic field as large as 100 T.
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Affiliation(s)
- Vladimir Voroshnin
- Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Strasse 24/25, Potsdam 14476, Germany
| | - Artem V Tarasov
- St. Petersburg State University, St. Petersburg 198504, Russia
| | - Kirill A Bokai
- St. Petersburg State University, St. Petersburg 198504, Russia
| | - Alla Chikina
- Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI 5232, Switzerland
| | - Boris V Senkovskiy
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, Köln 50937, Germany
| | - Niels Ehlen
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, Köln 50937, Germany
| | | | - Alexander Grüneis
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, Köln 50937, Germany
| | - Maxim Krivenkov
- Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin 12489, Germany
| | | | - Alexander Fedorov
- IFW Dresden, Leibniz Institute for Solid State and Materials Research, D-01171, Dresden 01069, Germany
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7
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Pramanik A, Thakur S, Singh B, Willke P, Wenderoth M, Hofsäss H, Di Santo G, Petaccia L, Maiti K. Anomalies at the Dirac Point in Graphene and Its Hole-Doped Compositions. PHYSICAL REVIEW LETTERS 2022; 128:166401. [PMID: 35522498 DOI: 10.1103/physrevlett.128.166401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
We study the properties of the Dirac states in SiC-graphene and its hole-doped compositions employing angle-resolved photoemission spectroscopy and density functional theory. The symmetry-selective measurements for the Dirac bands reveal their linearly dispersive behavior across the Dirac point which was termed as the anomalous region in earlier studies. No gap is observed even after boron substitution that reduced the carrier concentration significantly from 3.7×10^{13} cm^{-2} in SiC-graphene to 0.8×10^{13} cm^{-2} (5% doping). The anomalies at the Dirac point are attributed to the spectral width arising from the lifetime and momentum broadening in the experiments. The substitution of boron at the graphitic sites leads to a band renormalization and a shift of the Dirac point towards the Fermi level. The internal symmetries appear to be preserved in SiC-graphene even after significant boron substitutions. These results suggest that SiC-graphene is a good platform to realize exotic science as well as advanced technology where the carrier properties like concentration, mobility, etc., can be tuned keeping the Dirac fermionic properties protected.
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Affiliation(s)
- Arindam Pramanik
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Sangeeta Thakur
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Trieste, Italy
| | - Bahadur Singh
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Philip Willke
- IV. Physikalisches Institut, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Martin Wenderoth
- IV. Physikalisches Institut, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Hans Hofsäss
- II. Physikalisches Institut, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Giovanni Di Santo
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Trieste, Italy
| | - Luca Petaccia
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Trieste, Italy
| | - Kalobaran Maiti
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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8
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Zhang Q, Zeng R, Lu Y, Zhang J, Zhou W, Yu J. Machine learning-based prediction of the adsorption energy of CO on boron-doped graphene. NEW J CHEM 2022. [DOI: 10.1039/d2nj01278b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To accurately and quickly investigate the adsorption ability of different boron-doped graphene for CO, 1864 different sets of CO adsorption energy on boron-doped graphene were obtained by simulation, and an overall framework based on machine learning was proposed.
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Affiliation(s)
- Qingwei Zhang
- School of Artificial Intelligence, Chongqing University of Technology, Chongqing 401135, China
| | - Rui Zeng
- School of Artificial Intelligence, Chongqing University of Technology, Chongqing 401135, China
| | - Yunhua Lu
- School of Artificial Intelligence, Chongqing University of Technology, Chongqing 401135, China
| | - Junan Zhang
- School of Artificial Intelligence, Chongqing University of Technology, Chongqing 401135, China
| | - Wanji Zhou
- School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Jintao Yu
- School of Artificial Intelligence, Chongqing University of Technology, Chongqing 401135, China
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9
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Physi-Sorption of H2 on Pure and Boron–Doped Graphene Monolayers: A Dispersion–Corrected DFT Study. C — JOURNAL OF CARBON RESEARCH 2020. [DOI: 10.3390/c6010015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
High-surface-area carbons are of interest as potential candidates to store H2 for fuel–cell power applications. Earlier work has been ambiguous and inconclusive on the effect of boron doping on H2 binding energy. Here, we describe a systematic dispersion–corrected density functional theory study to evaluate the effect of boron doping. We observe some enhancement in H2 binding, due to the presence of a defect, such as terminal hydrogen or distortion from planarity, introduced by the inclusion of boron into a graphene ring, which creates hydrogen adsorption sites with slightly increased binding energy. The increase is from −5 kJ/mol H2 for the pure carbon matrix to −7 kJ/mol H2 for the boron–doped system with the boron content of ~7%. The H2 binding sites have little direct interaction with boron. However, the largest enhancement in physi-sorption energy is seen for systems, where H2 is confined between layers at a distance of about 7 Å, where the H2 binding nearly doubles to −11 kJ/mol H2. These findings suggest that interplanar nanoconfinement might be more effective in enhancing H2 binding. Smaller coronene model is shown to be beneficial for understanding the dependence of interaction energy on the structural configurations and preferential H2 binding sites.
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Feng L, Qin Z, Huang Y, Peng K, Wang F, Yan Y, Chen Y. Boron-, sulfur-, and phosphorus-doped graphene for environmental applications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 698:134239. [PMID: 31505340 DOI: 10.1016/j.scitotenv.2019.134239] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/21/2019] [Accepted: 09/01/2019] [Indexed: 06/10/2023]
Abstract
The control of environmental pollutants is a global concern. Recently, heteroatom-doped graphene has drawn increasing attention due to their widespread applications in removing and detecting environmental pollutants. Owing to the introduction of heteroatoms into pristine graphene, the properties of heteroatom-doped graphene have been significantly enhanced in physic, chemistry, and biology. This review focuses on the approaches for synthesis and characterization of boron-, sulfur-, and phosphorus-doped graphene and their applications in the fields of adsorption, catalysis, and detection for environmental pollutants. The mechanisms of environmental applications, including π-π interactions, complexation, hydrophobic interactions, electronic conductivity, and active sites and reactive radicals, are elaborated. Furthermore, the challenges associated with the use of heteroatom-doped graphene materials and their prospective applications are also proposed.
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Affiliation(s)
- Leiyu Feng
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, 1239 Siping Road, Shanghai 200092, China
| | - Zhiyi Qin
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Yujun Huang
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Kangshou Peng
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Feng Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Yuanyuan Yan
- College of Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng, 224002, China
| | - Yinguang Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, 1239 Siping Road, Shanghai 200092, China.
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11
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Effect of Doping Temperatures and Nitrogen Precursors on the Physicochemical, Optical, and Electrical Conductivity Properties of Nitrogen-Doped Reduced Graphene Oxide. MATERIALS 2019; 12:ma12203376. [PMID: 31623130 PMCID: PMC6829554 DOI: 10.3390/ma12203376] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 09/26/2019] [Accepted: 10/05/2019] [Indexed: 11/30/2022]
Abstract
The greatest challenge in graphene-based material synthesis is achieving large surface area of high conductivity. Thus, tuning physico-electrochemical properties of these materials is of paramount importance. An even greater problem is to obtain a desired dopant configuration which allows control over device sensitivity and enhanced reproducibility. In this work, substitutional doping of graphene oxide (GO) with nitrogen atoms to induce lattice–structural modification of GO resulted in nitrogen-doped reduced graphene oxide (N-rGO). The effect of doping temperatures and various nitrogen precursors on the physicochemical, optical, and conductivity properties of N-rGO is hereby reported. This was achieved by thermal treating GO with different nitrogen precursors at various doping temperatures. The lowest doping temperature (600 °C) resulted in less thermally stable N-rGO, yet with higher porosity, while the highest doping temperature (800 °C) produced the opposite results. The choice of nitrogen precursors had a significant impact on the atomic percentage of nitrogen in N-rGO. Nitrogen-rich precursor, 4-nitro-ο-phenylenediamine, provided N-rGO with favorable physicochemical properties (larger surface area of 154.02 m2 g−1) with an enhanced electrical conductivity (0.133 S cm−1) property, making it more useful in energy storage devices. Thus, by adjusting the doping temperatures and nitrogen precursors, one can tailor various properties of N-rGO.
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12
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Balog R, Cassidy A, Jørgensen J, Kyhl L, Andersen M, Čabo AG, Ravani F, Bignardi L, Lacovig P, Lizzit S, Hornekær L. Hydrogen interaction with graphene on Ir(1 1 1): a combined intercalation and functionalization study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:085001. [PMID: 30628585 DOI: 10.1088/1361-648x/aaf76b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We demonstrate a procedure for obtaining a H-intercalated graphene layer that is found to be chemically decoupled from the underlying metal substrate. Using high-resolution x-ray photoelectron spectroscopy and scanning tunneling microscopy techniques, we reveal that the hydrogen intercalated graphene is p-doped by about 0.28 eV, but also identify structures of interfacial hydrogen. Furthermore, we investigate the reactivity of the decoupled layer towards atomic hydrogen and vibrationally excited molecular hydrogen and compare these results to the case of non-intercalated graphene. We find distinct differences between the two. Finally, we discuss the possibility to form graphane clusters on an iridium substrate by combined intercalation and H atom exposure experiments.
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Affiliation(s)
- Richard Balog
- Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
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13
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Fedorov AV, Yashina LV, Vilkov OY, Laubschat C, Vyalikh DV, Usachov DY. Spin-polarized Fermi surface, hole-doping and band gap in graphene with boron impurities. NANOSCALE 2018; 10:22810-22817. [PMID: 30488051 DOI: 10.1039/c8nr08339h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Embedding foreign atoms in graphene and interchanging the underlying substrate are proved to be efficient methods for manipulating the properties of graphene. Combining ARPES experiments with DFT calculations we show that boron-doped graphene (B-graphene) grown on a Co(0001) substrate by chemical vapor deposition (CVD) becomes hole doped and its Fermi surface near the K-point reveals strongly spin-polarized states. The latter stems from the spin-polarized mini Dirac cone that is an intrinsic two-dimensional feature of the graphene/Co(0001) interface and is formed by a mixture of C 2pz and Co 3d states. Since the CVD method allows the achievement of up to 20 at% of incorporated B atoms, this provides a certain flexibility for handling the spin-polarized properties of the system. We also show that the bonding of the B-graphene layer to the Co(0001) substrate can be released by intercalation of Li into the interface. This allows the exploration of the doping effect in detail. Finally, our ARPES data indicate a gap opening in the Dirac cone as a result of the highly unbalanced boron concentrations in the two graphene sublattices.
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Affiliation(s)
- Alexander V Fedorov
- St. Petersburg State University, 7/9 Universitetskaya Nab., St Petersburg 199034, Russia. and IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany
| | - Lada V Yashina
- M.V. Lomonosov Moscow State University, Leninskie Gory 1/3, 199991 Moscow, Russia
| | - Oleg Yu Vilkov
- St. Petersburg State University, 7/9 Universitetskaya Nab., St Petersburg 199034, Russia.
| | - Clemens Laubschat
- Institute of Solid State and Materials Physics, Technische Universität Dresden, 01062 Dresden, Germany
| | - Denis V Vyalikh
- Donostia International Physics Center (DIPC), Departamento de Fisica de Materiales and CFM-MPC UPV/EHU, 20080 San Sebastian, Spain and IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
| | - Dmitry Yu Usachov
- St. Petersburg State University, 7/9 Universitetskaya Nab., St Petersburg 199034, Russia.
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Bulusheva LG, Okotrub AV, Yashina LV, Velasco-Velez JJ, Usachov DY, Vyalikh DV. X-ray photoelectron spectroscopy study of the interaction of lithium with graphene. PHYSICAL SCIENCES REVIEWS 2018. [DOI: 10.1515/psr-2018-0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Graphene-like nanostructures, solely or in combination with redox active compounds, are an important component of battery electrodes. Design of effective electrode materials requires a deep understanding of electrochemical reactions occurring at graphene surfaces. The methods of X-ray photoelectron spectroscopy (XPS) are very helpful in such research, providing the composition of studied samples and electronic state of individual elements. In this chapter, we demonstrate advantages of XPS for monitoring of chemical vapor deposition graphene growth and lithium penetration under graphene layers, disclosing of interactions with metals and interface states.
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15
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Senkovskiy BV, Usachov DY, Fedorov AV, Marangoni T, Haberer D, Tresca C, Profeta G, Caciuc V, Tsukamoto S, Atodiresei N, Ehlen N, Chen C, Avila J, Asensio MC, Varykhalov AY, Nefedov A, Wöll C, Kim TK, Hoesch M, Fischer FR, Grüneis A. Boron-Doped Graphene Nanoribbons: Electronic Structure and Raman Fingerprint. ACS NANO 2018; 12:7571-7582. [PMID: 30004663 DOI: 10.1021/acsnano.8b04125] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We investigate the electronic and vibrational properties of bottom-up synthesized aligned armchair graphene nanoribbons of N = 7 carbon atoms width periodically doped by substitutional boron atoms (B-7AGNRs). Using angle-resolved photoemission spectroscopy and density functional theory calculations, we find that the dopant-derived valence and conduction band states are notably hybridized with electronic states of Au substrate and spread in energy. The interaction with the substrate leaves the bands with pure carbon character rather unperturbed. This results in an identical effective mass of ≈0.2 m0 for the next-highest valence band compared with pristine 7AGNRs. We probe the phonons of B-7AGNRs by ultrahigh-vacuum (UHV) Raman spectroscopy and reveal the existence of characteristic splitting and red shifts in Raman modes due to the presence of substitutional boron atoms. Comparing the Raman spectra for three visible lasers (red, green, and blue), we find that interaction with gold suppresses the Raman signal from B-7AGNRs and the energy of the green laser (2.33 eV) is closer to the resonant E22 transition. The hybridized electronic structure of the B-7AGNR-Au interface is expected to improve electrical characteristics of contacts between graphene nanoribbon and Au. The Raman fingerprint allows the easy identification of B-7AGNRs, which is particularly useful for device fabrication.
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Affiliation(s)
- Boris V Senkovskiy
- II. Physikalisches Institut, Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Dmitry Yu Usachov
- St. Petersburg State University , 7/9 Universitetskaya nab. , Saint Petersburg 199034 , Russia
| | - Alexander V Fedorov
- II. Physikalisches Institut, Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
- St. Petersburg State University , 7/9 Universitetskaya nab. , Saint Petersburg 199034 , Russia
- IFW Dresden , P.O. Box 270116, D-01171 Dresden , Germany
| | - Tomas Marangoni
- Department of Chemistry , University of California , Tan Hall 680 , Berkeley , California 94720 , United States
| | - Danny Haberer
- Department of Chemistry , University of California , Tan Hall 680 , Berkeley , California 94720 , United States
| | - Cesare Tresca
- Department of Physical and Chemical Sciences and SPIN-CNR , University of L'Aquila , Via Vetoio 10 , I-67100 Coppito , Italy
- Institut des Nanosciences de Paris, Sorbonne Universités-UPMC univ Paris 6 and CNRS-UMR 7588 , 4 place Jussieu , F-75252 Paris , France
| | - Gianni Profeta
- Department of Physical and Chemical Sciences and SPIN-CNR , University of L'Aquila , Via Vetoio 10 , I-67100 Coppito , Italy
| | - Vasile Caciuc
- Peter Grünberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1) , Forschungszentrum Jülich and JARA , D-52425 Jülich , Germany
| | - Shigeru Tsukamoto
- Peter Grünberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1) , Forschungszentrum Jülich and JARA , D-52425 Jülich , Germany
| | - Nicolae Atodiresei
- Peter Grünberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1) , Forschungszentrum Jülich and JARA , D-52425 Jülich , Germany
| | - Niels Ehlen
- II. Physikalisches Institut, Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Chaoyu Chen
- ANTARES Beamline , Synchrotron SOLEIL & Universite Paris-Saclay, L' Orme des Merisiers , Saint Aubin-BP 48 , 91192 Gif sur Yvette Cedex , France
| | - José Avila
- ANTARES Beamline , Synchrotron SOLEIL & Universite Paris-Saclay, L' Orme des Merisiers , Saint Aubin-BP 48 , 91192 Gif sur Yvette Cedex , France
| | - Maria C Asensio
- ANTARES Beamline , Synchrotron SOLEIL & Universite Paris-Saclay, L' Orme des Merisiers , Saint Aubin-BP 48 , 91192 Gif sur Yvette Cedex , France
| | | | - Alexei Nefedov
- Institut für Funktionelle Grenzflächen (IFG), Karlsruher Institut für Technologie (KIT) , Hermann-von-Helmholtz-Platz 1 , 76344 Eggenstein-Leopoldshafen , Germany
| | - Christof Wöll
- Institut für Funktionelle Grenzflächen (IFG), Karlsruher Institut für Technologie (KIT) , Hermann-von-Helmholtz-Platz 1 , 76344 Eggenstein-Leopoldshafen , Germany
| | - Timur K Kim
- Diamond Light Source, Harwell Campus , Didcot , OX11 0DE , United Kingdom
| | - Moritz Hoesch
- Diamond Light Source, Harwell Campus , Didcot , OX11 0DE , United Kingdom
- DESY Photon Science, Deutsches Elektronen-Synchrotron , Notkestrasse 85 , 22607 Hamburg , Germany
| | - Felix R Fischer
- Department of Chemistry , University of California , Tan Hall 680 , Berkeley , California 94720 , United States
- Materials Science Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Kavli Energy Nanosciences Institute at the University of California Berkeley and Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Alexander Grüneis
- II. Physikalisches Institut, Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
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16
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Usachov DY, Bokai KA, Marchenko DE, Fedorov AV, Shevelev VO, Vilkov OY, Kataev EY, Yashina LV, Rühl E, Laubschat C, Vyalikh DV. Cobalt-assisted recrystallization and alignment of pure and doped graphene. NANOSCALE 2018; 10:12123-12132. [PMID: 29915820 DOI: 10.1039/c8nr03183e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Recrystallization of bulk materials is a well-known phenomenon, which is widely used in commercial manufacturing. However, for low-dimensional materials like graphene, this process still remains an unresolved puzzle. Thus, the understanding of the underlying mechanisms and the required conditions for recrystallization in low dimensions is essential for the elaboration of routes towards the inexpensive and reliable production of high-quality nanomaterials. Here, we unveil the details of the efficient recrystallization of one-atom-thick pure and boron-doped polycrystalline graphene layers on a Co(0001) surface. By applying photoemission and electron diffraction, we show how more than 90% of the initially misoriented graphene grains can be reconstructed into a well-oriented and single-crystalline layer. The obtained recrystallized graphene/Co interface exhibits high structural quality with a pronounced sublattice asymmetry, which is important for achieving an unbalanced sublattice doping of graphene. By exploring the kinetics of recrystallization for native and B-doped graphene on Co, we were able to estimate the activation energy and propose a mechanism of this process.
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Affiliation(s)
- Dmitry Yu Usachov
- St. Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia.
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17
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M. Dieb T, Hou Z, Tsuda K. Structure prediction of boron-doped graphene by machine learning. J Chem Phys 2018; 148:241716. [DOI: 10.1063/1.5018065] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Thaer M. Dieb
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
- National Institute for Materials Science (NIMS), Tsukuba, Japan
- RIKEN, Center for Advanced Intelligence Project, Tokyo, Japan
| | - Zhufeng Hou
- National Institute for Materials Science (NIMS), Tsukuba, Japan
| | - Koji Tsuda
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
- National Institute for Materials Science (NIMS), Tsukuba, Japan
- RIKEN, Center for Advanced Intelligence Project, Tokyo, Japan
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18
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Rybkin AG, Rybkina AA, Otrokov MM, Vilkov OY, Klimovskikh II, Petukhov AE, Filianina MV, Voroshnin VY, Rusinov IP, Ernst A, Arnau A, Chulkov EV, Shikin AM. Magneto-Spin-Orbit Graphene: Interplay between Exchange and Spin-Orbit Couplings. NANO LETTERS 2018; 18:1564-1574. [PMID: 29365269 DOI: 10.1021/acs.nanolett.7b01548] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A rich class of spintronics-relevant phenomena require implementation of robust magnetism and/or strong spin-orbit coupling (SOC) to graphene, but both properties are completely alien to it. Here, we for the first time experimentally demonstrate that a quasi-freestanding character, strong exchange splitting and giant SOC are perfectly achievable in graphene at once. Using angle- and spin-resolved photoemission spectroscopy, we show that the Dirac state in the Au-intercalated graphene on Co(0001) experiences giant splitting (up to 0.2 eV) while being by no means distorted due to interaction with the substrate. Our calculations, based on the density functional theory, reveal the splitting to stem from the combined action of the Co thin film in-plane exchange field and Au-induced Rashba SOC. Scanning tunneling microscopy data suggest that the peculiar reconstruction of the Au/Co(0001) interface is responsible for the exchange field transfer to graphene. The realization of this "magneto-spin-orbit" version of graphene opens new frontiers for both applied and fundamental studies using its unusual electronic bandstructure.
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Affiliation(s)
- Artem G Rybkin
- Research Park , Saint Petersburg State University , 198504 Saint Petersburg , Russia
| | - Anna A Rybkina
- Saint Petersburg State University , 198504 Saint Petersburg , Russia
| | - Mikhail M Otrokov
- Saint Petersburg State University , 198504 Saint Petersburg , Russia
- Donostia International Physics Center (DIPC) , Paseo de Manuel Lardizabal 4 , 20018 San Sebastián/Donostia , Spain
- Tomsk State University , 634050 Tomsk , Russia
- Departamento de Física de Materiales UPV/EHU , Centro de Física de Materiales CFM - MPC and Centro Mixto CSIC-UPV/EHU , 20080 San Sebastián/Donostia , Spain
| | - Oleg Yu Vilkov
- Saint Petersburg State University , 198504 Saint Petersburg , Russia
| | | | | | - Maria V Filianina
- Saint Petersburg State University , 198504 Saint Petersburg , Russia
| | | | - Igor P Rusinov
- Saint Petersburg State University , 198504 Saint Petersburg , Russia
- Tomsk State University , 634050 Tomsk , Russia
| | - Arthur Ernst
- Max-Planck-Institut für Mikrostrukturphysik , Weinberg 2 , D-06120 Halle , Germany
- Institut für Theoretische Physik, Johannes Kepler Universität , A 4040 Linz , Austria
| | - Andrés Arnau
- Donostia International Physics Center (DIPC) , Paseo de Manuel Lardizabal 4 , 20018 San Sebastián/Donostia , Spain
- Departamento de Física de Materiales UPV/EHU , Centro de Física de Materiales CFM - MPC and Centro Mixto CSIC-UPV/EHU , 20080 San Sebastián/Donostia , Spain
| | - Evgueni V Chulkov
- Saint Petersburg State University , 198504 Saint Petersburg , Russia
- Donostia International Physics Center (DIPC) , Paseo de Manuel Lardizabal 4 , 20018 San Sebastián/Donostia , Spain
- Tomsk State University , 634050 Tomsk , Russia
- Departamento de Física de Materiales UPV/EHU , Centro de Física de Materiales CFM - MPC and Centro Mixto CSIC-UPV/EHU , 20080 San Sebastián/Donostia , Spain
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19
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Usachov DY, Davydov VY, Levitskii VS, Shevelev VO, Marchenko D, Senkovskiy BV, Vilkov OY, Rybkin AG, Yashina LV, Chulkov EV, Sklyadneva IY, Heid R, Bohnen KP, Laubschat C, Vyalikh DV. Raman Spectroscopy of Lattice-Matched Graphene on Strongly Interacting Metal Surfaces. ACS NANO 2017; 11:6336-6345. [PMID: 28494148 DOI: 10.1021/acsnano.7b02686] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Regardless of the widely accepted opinion that there is no Raman signal from single-layer graphene when it is strongly bonded to a metal surface, we present Raman spectra of a graphene monolayer on Ni(111) and Co(0001) substrates. The high binding energy of carbon to these surfaces allows formation of lattice-matched (1 × 1) structures where graphene is significantly stretched. This is reflected in a record-breaking shift of the Raman G band by more than 100 cm-1 relative to the case of freestanding graphene. Using electron diffraction and photoemission spectroscopy, we explore the aforementioned systems together with polycrystalline graphene on Co and analyze possible intercalation of oxygen at ambient conditions. The results obtained are fully supported by Raman spectroscopy. Performing a theoretical investigation of the phonon dispersions of freestanding graphene and stretched graphene on the strongly interacting Co surface, we explain the main features of the Raman spectra. Our results create a reliable platform for application of Raman spectroscopy in diagnostics of chemisorbed graphene and related materials.
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Affiliation(s)
- Dmitry Yu Usachov
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Valery Yu Davydov
- Ioffe Physical Technical Institute , St. Petersburg, 194021, Russia
- ITMO University , St. Petersburg, 197101, Russia
| | | | - Viktor O Shevelev
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Dmitry Marchenko
- Helmholtz-Zentrum Berlin für Materialien und Energie , 14109 Berlin, Germany
| | - Boris V Senkovskiy
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
- II Physikalisches Institut, Universität zu Köln , Zülpicher Straße 77, 50937 Köln, Germany
| | - Oleg Yu Vilkov
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Artem G Rybkin
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Lada V Yashina
- M.V. Lomonosov Moscow State University , Leninskie Gory 1/3, 199991 Moscow, Russia
| | - Evgueni V Chulkov
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
- Departamento de Fisica de Materiales and CFM-MPC UPV/EHU, Donostia International Physics Center (DIPC) , 20080 San Sebastian, Spain
| | - Irina Yu Sklyadneva
- Departamento de Fisica de Materiales and CFM-MPC UPV/EHU, Donostia International Physics Center (DIPC) , 20080 San Sebastian, Spain
- Tomsk State University , Lenina Avenue, 36, 634050 Tomsk, Russia
- Institut für Festkörperphysik, Karlsruher Institut für Technologie , D-76021 Karlsruhe, Germany
- Institute of Strength Physics and Materials Science , pr. Academicheskii 2/1, 634021, Tomsk, Russian Federation
| | - Rolf Heid
- Institut für Festkörperphysik, Karlsruher Institut für Technologie , D-76021 Karlsruhe, Germany
| | - Klaus-Peter Bohnen
- Institut für Festkörperphysik, Karlsruher Institut für Technologie , D-76021 Karlsruhe, Germany
| | - Clemens Laubschat
- Institute of Solid State Physics, Dresden University of Technology , 01062 Dresden, Germany
| | - Denis V Vyalikh
- St. Petersburg State University , 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
- Departamento de Fisica de Materiales and CFM-MPC UPV/EHU, Donostia International Physics Center (DIPC) , 20080 San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science , 48011 Bilbao, Spain
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