1
|
Noordhoek K, Bartel CJ. Accelerating the prediction of inorganic surfaces with machine learning interatomic potentials. NANOSCALE 2024. [PMID: 38470833 DOI: 10.1039/d3nr06468a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
The surface properties of solid-state materials often dictate their functionality, especially for applications where nanoscale effects become important. The relevant surface(s) and their properties are determined, in large part, by the material's synthesis or operating conditions. These conditions dictate thermodynamic driving forces and kinetic rates responsible for yielding the observed surface structure and morphology. Computational surface science methods have long been applied to connect thermochemical conditions to surface phase stability, particularly in the heterogeneous catalysis and thin film growth communities. This review provides a brief introduction to first-principles approaches to compute surface phase diagrams before introducing emerging data-driven approaches. The remainder of the review focuses on the application of machine learning, predominantly in the form of learned interatomic potentials, to study complex surfaces. As machine learning algorithms and large datasets on which to train them become more commonplace in materials science, computational methods are poised to become even more predictive and powerful for modeling the complexities of inorganic surfaces at the nanoscale.
Collapse
Affiliation(s)
- Kyle Noordhoek
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, 55455, USA.
| | - Christopher J Bartel
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, 55455, USA.
| |
Collapse
|
2
|
Grubišić-Čabo A, Michiardi M, Sanders CE, Bianchi M, Curcio D, Phuyal D, Berntsen MH, Guo Q, Dendzik M. In Situ Exfoliation Method of Large-Area 2D Materials. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023:e2301243. [PMID: 37236159 PMCID: PMC10401183 DOI: 10.1002/advs.202301243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Indexed: 05/28/2023]
Abstract
2D materials provide a rich platform to study novel physical phenomena arising from quantum confinement of charge carriers. Many of these phenomena are discovered by surface sensitive techniques, such as photoemission spectroscopy, that work in ultra-high vacuum (UHV). Success in experimental studies of 2D materials, however, inherently relies on producing adsorbate-free, large-area, high-quality samples. The method that yields 2D materials of highest quality is mechanical exfoliation from bulk-grown samples. However, as this technique is traditionally performed in a dedicated environment, the transfer of samples into vacuum requires surface cleaning that might diminish the quality of the samples. In this article, a simple method for in situ exfoliation directly in UHV is reported, which yields large-area, single-layered films. Multiple metallic and semiconducting transition metal dichalcogenides are exfoliated in situ onto Au, Ag, and Ge. The exfoliated flakes are found to be of sub-millimeter size with excellent crystallinity and purity, as supported by angle-resolved photoemission spectroscopy, atomic force microscopy, and low-energy electron diffraction. The approach is well-suited for air-sensitive 2D materials, enabling the study of a new suite of electronic properties. In addition, the exfoliation of surface alloys and the possibility of controlling the substrate-2D material twist angle is demonstrated.
Collapse
Affiliation(s)
- Antonija Grubišić-Čabo
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, 9747 AG, The Netherlands
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Matteo Michiardi
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Charlotte E Sanders
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, 0X11 0QX, UK
| | - Marco Bianchi
- School of Physics and Astronomy, Aarhus University, Aarhus, 8000 C, Denmark
| | - Davide Curcio
- School of Physics and Astronomy, Aarhus University, Aarhus, 8000 C, Denmark
| | - Dibya Phuyal
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Magnus H Berntsen
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Qinda Guo
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Maciej Dendzik
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| |
Collapse
|
3
|
Zhang Y, Liu H, Zhao Y, Lin J, Bai Y, Zhao J, Gao J. The effects of intercalated environmental gas molecules on carrier dynamics in WSe 2/WS 2 heterostructures. MATERIALS HORIZONS 2023. [PMID: 37074810 DOI: 10.1039/d3mh00420a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Effective tuning of carrier dynamics in two-dimensional (2D) materials is significant for multi-scene device applications. Using first-principles and ab initio nonadiabatic molecular dynamics calculations, the kinetics of O2, H2O, and N2 intercalation into 2D WSe2/WS2 van der Waals heterostructures and its effect on carrier dynamics have been comprehensively explored. It is found that the O2 molecule prefers to dissociate into atomic O atoms spontaneously after intercalation of WSe2/WS2 heterostructures, whereas H2O and N2 molecules remain intact. O2 intercalation significantly speeds up the electron separation process, while H2O intercalation largely speeds up the hole separation process. The lifetime of excited carriers can be prolonged by O2 or H2O or N2 intercalations. These intriguing phenomena can be attributed to the effect of interlayer coupling, and the underlying physical mechanism for tuning the carrier dynamics is fully discussed. Our results provide useful guidance for the experimental design of 2D heterostructures for optoelectronic applications in photocatalysts and solar energy cells.
Collapse
Affiliation(s)
- Yanxue Zhang
- State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment (Dalian University of Technology), Ministry of Education, Dalian, 116024, China.
| | - Hongsheng Liu
- Key laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian, 116024, China
| | - Yanyan Zhao
- State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment (Dalian University of Technology), Ministry of Education, Dalian, 116024, China.
| | - Jiaqi Lin
- The School of Bioengineering, Dalian University of Technology, Dalian, 116024, China.
| | - Yizhen Bai
- Key laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian, 116024, China
| | - Jijun Zhao
- State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment (Dalian University of Technology), Ministry of Education, Dalian, 116024, China.
- Key laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian, 116024, China
| | - Junfeng Gao
- State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment (Dalian University of Technology), Ministry of Education, Dalian, 116024, China.
- Key laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian, 116024, China
| |
Collapse
|
4
|
Zhang K, Ban C, Yuan Y, Huang L, Gan Y. Nanoscale imaging of oxidized copper foil covered with CVD‐grown graphene layers. SURF INTERFACE ANAL 2022. [DOI: 10.1002/sia.7096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Kai Zhang
- School of Electronics and Information Engineering Hebei University of Technology Tianjin P. R. China
| | - Chun‐guang Ban
- School of Materials Science and Technology Hebei University of Technology Tianjin P. R. China
| | - Ye Yuan
- School of Materials Science and Technology Hebei University of Technology Tianjin P. R. China
| | - Li Huang
- School of Electronics and Information Engineering Hebei University of Technology Tianjin P. R. China
| | - Yang Gan
- School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin P. R. China
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin P. R. China
| |
Collapse
|
5
|
Grånäs E, Schröder UA, Arman MA, Andersen M, Gerber T, Schulte K, Andersen JN, Michely T, Hammer B, Knudsen J. Water Chemistry beneath Graphene: Condensation of a Dense OH-H 2O Phase under Graphene. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:4347-4354. [PMID: 35299819 PMCID: PMC8919254 DOI: 10.1021/acs.jpcc.1c10289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/12/2022] [Indexed: 06/14/2023]
Abstract
Room temperature oxygen hydrogenation below graphene flakes supported by Ir(111) is investigated through a combination of X-ray photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory calculations using an evolutionary search algorithm. We demonstrate how the graphene cover and its doping level can be used to trap and characterize dense mixed O-OH-H2O phases that otherwise would not exist. Our study of these graphene-stabilized phases and their response to oxygen or hydrogen exposure reveals that additional oxygen can be dissolved into them at room temperature creating mixed O-OH-H2O phases with an increased areal coverage underneath graphene. In contrast, additional hydrogen exposure converts the mixed O-OH-H2O phases back to pure OH-H2O with a reduced areal coverage underneath graphene.
Collapse
Affiliation(s)
- Elin Grånäs
- Division
of Synchrotron Radiation Research, Department of Physics, Lund University, Box
118, 221 00 Lund, Sweden
- Deutsches
Elektronen-Synchrotron (DESY), 22607 Hamburg, Germany
| | | | - Mohammad A. Arman
- Division
of Synchrotron Radiation Research, Department of Physics, Lund University, Box
118, 221 00 Lund, Sweden
| | - Mie Andersen
- Aarhus
Institute of Advanced Studies, Aarhus University, Aarhus C, DK-8000 Denmark
- Department
of Physics and Astronomy - Center for Interstellar Catalysis, Aarhus University, Aarhus C, DK-8000 Denmark
| | - Timm Gerber
- II.
Physikalisches Institut, Universität
zu Köln, 50937 Köln, Germany
| | - Karina Schulte
- MAX
IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
| | - Jesper N. Andersen
- MAX
IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
- Division
of Synchrotron Radiation Research, Department of Physics, Lund University, Box
118, 221 00 Lund, Sweden
| | - Thomas Michely
- II.
Physikalisches Institut, Universität
zu Köln, 50937 Köln, Germany
| | - Bjørk Hammer
- Aarhus
Institute of Advanced Studies, Aarhus University, Aarhus C, DK-8000 Denmark
- Department
of Physics and Astronomy - Center for Interstellar Catalysis, Aarhus University, Aarhus C, DK-8000 Denmark
| | - Jan Knudsen
- MAX
IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
- Division
of Synchrotron Radiation Research, Department of Physics, Lund University, Box
118, 221 00 Lund, Sweden
| |
Collapse
|
6
|
Corrosion Resistance of Ultrathin Two-Dimensional Coatings: First-Principles Calculations towards In-Depth Mechanism Understanding and Precise Material Design. METALS 2021. [DOI: 10.3390/met11122011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In recent years, ultrathin two-dimensional (2D) coatings, e.g., graphene (Gr) and hexagonal boron nitride (h-BN), are intriguing research foci in the field of anticorrosion because their high air stability, excellent impermeability, high optical transparency, and atomistic thickness have endowed them with attractive anticorrosion applications. The microstructure of 2D coatings, coating–substrate interactions, and properties of 2D coatings on substrates in a variety of environmental conditions (e.g., at different temperatures, stresses, and pH values) are the key factors governing the anticorrosion performance of 2D coatings and are among the central topics for all 2D-coating studies. For many conventional experimental measurements (e.g., microscopy and electrochemical methods), there exist challenges to acquire detailed information on the atomistic mechanisms for the involved subnanometer scale corrosion problems. Alternatively, as a precise and efficient quantum-mechanical simulation approach, the first-principles calculation based on density-functional theory (DFT) has become a powerful way to study the thermodynamic and kinetic properties of materials on the atomic scale, as well as to clearly reveal the underlying microscopic mechanisms. In this review, we introduce the anticorrosion performance, existing problems, and optimization ways of Gr and h-BN coatings and summarize important recent DFT results on the critical and complex roles of coating defects and coating–substrate interfaces in governing their corrosion resistance. These DFT progresses have shed much light on the optimization ways towards better anticorrosion 2D coatings and also guided us to make a prospect on the further development directions and promising design schemes for superior anticorrosion ultrathin 2D coatings in the future.
Collapse
|
7
|
Bouheddadj A, Ouahrani T, Kanhounnon WG, Reda BM, Bedrane S, Badawi M, Morales-García Á. Low-dimensional HfS 2 as SO 2 adsorbent and gas sensor: effect of water and sulfur vacancies. Phys Chem Chem Phys 2021; 23:23655-23666. [PMID: 34664566 DOI: 10.1039/d1cp04069c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
First-principles based on density functional theory (DFT) calculations were performed to investigate the interaction of two-dimensional (2D) HfS2 with SO2, a harmful gas with implications for climate change. In particular, we describe the effect of water and sulfur vacancies on such interaction. The former promotes the physisorption of SO2, whereas the latter promotes its chemisorption with structural changes on the absorbing surface. The results show that both structures are exothermic to adsorb the SO2 molecules, but the adsorption type is different. The reaction of the stable structure in the presence of water with the sulfur oxides is a physisorption interaction that enhances the band gap value of the isolated monolayer. However, for the defective structure, we have a chemisorption interaction type, where the adsorption of SO2 molecules widens the band gap values. To understand this behavior, we used Bader charge calculations and the noncovalent interactions index. While the water enhances the charge transfer between the monolayer and the adsorbed gas, the results show, however, that the defective structure is a more favorable gas sensor due to the metallic edge of the active site.
Collapse
Affiliation(s)
- Amina Bouheddadj
- Laboratoire de Physique Théorique, Université de Tlemcen, 1300, Algeria.
| | - Tarik Ouahrani
- Laboratoire de Physique Théorique, Université de Tlemcen, 1300, Algeria.
| | - Wilfried G Kanhounnon
- Laboratoire de Chimie Théorique et de Spectroscopie Moléculaire (LACTHESMO), Université dAbomey-Calavi, Benin
| | - Boufatah M Reda
- Laboratoire de Physique Théorique, Université de Tlemcen, 1300, Algeria.
| | - Sumeya Bedrane
- Laboratory of Catalysis and Synthesis in Organic Chemistry, University of Tlemcen, Tlemcen, BP 119, Algeria
| | - Michael Badawi
- Université de Lorraine and CNRS, LPCT, UMR 7019, 54506 Vandoeuvre-lés-Nancy, France
| | - Ángel Morales-García
- Departamentde Ciènciade Materials i Química Física & Institutde Química Teórica i Computacional (IQTCUB) Universitatde Barcelona, c/Martíi Franquès 1-11, 08028, Barcelona, Spain.
| |
Collapse
|
8
|
Røst HI, Reed BP, Strand FS, Durk JA, Evans DA, Grubišić-Čabo A, Wan G, Cattelan M, Prieto MJ, Gottlob DM, Tănase LC, de Souza Caldas L, Schmidt T, Tadich A, Cowie BCC, Chellappan RK, Wells JW, Cooil SP. A Simplified Method for Patterning Graphene on Dielectric Layers. ACS APPLIED MATERIALS & INTERFACES 2021; 13:37510-37516. [PMID: 34328712 PMCID: PMC8365599 DOI: 10.1021/acsami.1c09987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
The large-scale formation of patterned, quasi-freestanding graphene structures supported on a dielectric has so far been limited by the need to transfer the graphene onto a suitable substrate and contamination from the associated processing steps. We report μm scale, few-layer graphene structures formed at moderate temperatures (600-700 °C) and supported directly on an interfacial dielectric formed by oxidizing Si layers at the graphene/substrate interface. We show that the thickness of this underlying dielectric support can be tailored further by an additional Si intercalation of the graphene prior to oxidation. This produces quasi-freestanding, patterned graphene on dielectric SiO2 with a tunable thickness on demand, thus facilitating a new pathway to integrated graphene microelectronics.
Collapse
Affiliation(s)
- Håkon I. Røst
- Center
for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Benjamen P. Reed
- Department
of Physics, Aberystwyth University, Aberystwyth SY23 3BZ, United Kingdom
| | - Frode S. Strand
- Center
for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Joseph A. Durk
- Department
of Physics, Aberystwyth University, Aberystwyth SY23 3BZ, United Kingdom
| | - D. Andrew Evans
- Department
of Physics, Aberystwyth University, Aberystwyth SY23 3BZ, United Kingdom
| | - Antonija Grubišić-Čabo
- School
of Physics & Astronomy, Monash University, 1 Wellington Rd., Clayton, Victoria 3800, Australia
| | - Gary Wan
- School
of Physics, HH Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, United Kingdom
| | - Mattia Cattelan
- School
of Chemistry, University of Bristol, Cantocks Close, Bristol BS8 1TS, United
Kingdom
| | - Mauricio J. Prieto
- Department
of Interface Science, Fritz-Haber-Institute
of the Max-Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Daniel M. Gottlob
- Department
of Interface Science, Fritz-Haber-Institute
of the Max-Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Liviu C. Tănase
- Department
of Interface Science, Fritz-Haber-Institute
of the Max-Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Lucas de Souza Caldas
- Department
of Interface Science, Fritz-Haber-Institute
of the Max-Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Thomas Schmidt
- Department
of Interface Science, Fritz-Haber-Institute
of the Max-Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
| | - Anton Tadich
- Australian
Synchrotron, 800 Blackburn
Rd., Clayton, Victoria 3168, Australia
| | - Bruce C. C. Cowie
- Australian
Synchrotron, 800 Blackburn
Rd., Clayton, Victoria 3168, Australia
| | - Rajesh Kumar Chellappan
- Center
for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Justin W. Wells
- Center
for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
- Semiconductor
Physics, Department of Physics, University
of Oslo (UiO), NO-0371 Oslo, Norway
| | - Simon P. Cooil
- Department
of Physics, Aberystwyth University, Aberystwyth SY23 3BZ, United Kingdom
- Semiconductor
Physics, Department of Physics, University
of Oslo (UiO), NO-0371 Oslo, Norway
| |
Collapse
|
9
|
Apostol NG, Bucur IC, Lungu GA, Tache CA, Teodorescu CM. CO adsorption and oxidation at room temperature on graphene synthesized on atomically clean Pt(001). Catal Today 2021. [DOI: 10.1016/j.cattod.2020.02.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
10
|
Barreto L, Henrique de Lima L, Coutinho Martins D, Silva C, Cezar de Campos Ferreira R, Landers R, de Siervo A. Selecting 'convenient observers' to probe the atomic structure of CVD graphene on Ir(111) via photoelectron diffraction. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:105001. [PMID: 33254156 DOI: 10.1088/1361-648x/abceff] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
CVD graphene grown on metallic substrates presents, in several cases, a long-range periodic structure due to a lattice mismatch between the graphene and the substrate. For instance, graphene grown on Ir(111), displays a corrugated supercell with distinct adsorption sites due to a variation of its local electronic structure. This type of surface reconstruction represents a challenging problem for a detailed atomic surface structure determination for experimental and theoretical techniques. In this work, we revisited the surface structure determination of graphene on Ir(111) by using the unique advantage of surface and chemical selectivity of synchrotron-based photoelectron diffraction. We take advantage of the Ir 4f photoemission surface state and use its diffraction signal as a probe to investigate the atomic arrangement of the graphene topping layer. We determine the average height and the overall corrugation of the graphene layer, which are respectively equal to 3.40 ± 0.11 Å and 0.45 ± 0.03 Å. Furthermore, we explore the graphene topography in the vicinity of its high-symmetry adsorption sites and show that the experimental data can be described by three reduced systems simplifying the moiré supercell multiple scattering analysis.
Collapse
Affiliation(s)
- Lucas Barreto
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André 09210-580, SP, Brazil
| | - Luis Henrique de Lima
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André 09210-580, SP, Brazil
| | - Daniel Coutinho Martins
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André 09210-580, SP, Brazil
| | - Caio Silva
- Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas 13083-859, SP, Brazil
| | | | - Richard Landers
- Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas 13083-859, SP, Brazil
| | - Abner de Siervo
- Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas 13083-859, SP, Brazil
| |
Collapse
|
11
|
Zhu S, Scardamaglia M, Kundsen J, Sankari R, Tarawneh H, Temperton R, Pickworth L, Cavalca F, Wang C, Tissot H, Weissenrieder J, Hagman B, Gustafson J, Kaya S, Lindgren F, Källquist I, Maibach J, Hahlin M, Boix V, Gallo T, Rehman F, D’Acunto G, Schnadt J, Shavorskiy A. HIPPIE: a new platform for ambient-pressure X-ray photoelectron spectroscopy at the MAX IV Laboratory. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:624-636. [PMID: 33650575 PMCID: PMC7941293 DOI: 10.1107/s160057752100103x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 01/28/2021] [Indexed: 05/28/2023]
Abstract
HIPPIE is a soft X-ray beamline on the 3 GeV electron storage ring of the MAX IV Laboratory, equipped with a novel ambient-pressure X-ray photoelectron spectroscopy (APXPS) instrument. The endstation is dedicated to performing in situ and operando X-ray photoelectron spectroscopy experiments in the presence of a controlled gaseous atmosphere at pressures up to 30 mbar [1 mbar = 100 Pa] as well as under ultra-high-vacuum conditions. The photon energy range is 250 to 2200 eV in planar polarization and with photon fluxes >1012 photons s-1 (500 mA ring current) at a resolving power of greater than 10000 and up to a maximum of 32000. The endstation currently provides two sample environments: a catalysis cell and an electrochemical/liquid cell. The former allows APXPS measurements of solid samples in the presence of a gaseous atmosphere (with a mixture of up to eight gases and a vapour of a liquid) and simultaneous analysis of the inlet/outlet gas composition by online mass spectrometry. The latter is a more versatile setup primarily designed for APXPS at the solid-liquid (dip-and-pull setup) or liquid-gas (liquid microjet) interfaces under full electrochemical control, and it can also be used as an open port for ad hoc-designed non-standard APXPS experiments with different sample environments. The catalysis cell can be further equipped with an IR reflection-absorption spectrometer, allowing for simultaneous APXPS and IR spectroscopy of the samples. The endstation is set up to easily accommodate further sample environments.
Collapse
Affiliation(s)
- Suyun Zhu
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
| | | | - Jan Kundsen
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Rami Sankari
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
- Department of Physics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere, Finland
| | - Hamed Tarawneh
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
| | - Robert Temperton
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
| | - Louisa Pickworth
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
| | - Filippo Cavalca
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
| | - Chunlei Wang
- Material Physics, School of Engineering Sciences, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Héloïse Tissot
- Material Physics, School of Engineering Sciences, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Jonas Weissenrieder
- Material Physics, School of Engineering Sciences, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Benjamin Hagman
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Johan Gustafson
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Sarp Kaya
- Department of Chemistry, Koc University, Istanbul 34450, Turkey
| | - Fredrik Lindgren
- Department of Physics and Astronomy, Division of Molecular and Condensed Matter Physics, Uppsala University, 751 20 Uppsala, Sweden
| | - Ida Källquist
- Department of Physics and Astronomy, Division of Molecular and Condensed Matter Physics, Uppsala University, 751 20 Uppsala, Sweden
| | - Julia Maibach
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Maria Hahlin
- Department of Physics and Astronomy, Division of Molecular and Condensed Matter Physics, Uppsala University, 751 20 Uppsala, Sweden
- Department of Chemistry – Ångström Laboratory, Uppsala University, Box 538, 751 21 Uppsala, Sweden
| | - Virginia Boix
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Tamires Gallo
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Foqia Rehman
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Giulio D’Acunto
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | - Joachim Schnadt
- MAX IV Laboratory, Lund University, Box 118, 221 00 Lund, Sweden
- Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden
| | | |
Collapse
|
12
|
Liu J, Zhang Y, Zhang H, Yang J. Mechanical properties of graphene-reinforced aluminium composite with modified substrate surface: a molecular dynamics study. NANOTECHNOLOGY 2021; 32:085712. [PMID: 33142279 DOI: 10.1088/1361-6528/abc712] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Due to its extraordinary properties, graphene has been widely used as reinforcing nanofillers to enhance the mechanical properties of polymer- or metal-based composites. However, the weak interfacial interaction between the matrix and graphene is still a major bottleneck that considerably hinders its reinforcing effectiveness and efficiency. This study presents an atomistic study via molecular dynamics simulation on a chemical modification strategy where the aluminium (Al) substrate is modified with Al2O3 (with or without covalent bonds formed between Al2O3 and graphene) or Al4C3 to achieve significantly improved interfacial shear strength and overall mechanical properties of graphene-reinforced aluminium (Al/Gr) composites. Numerical results show that this strategy works very well and among the three cases considered, modifying Al substrate by Al2O3 without covalent bonds formed at the interface between Al2O3 and graphene produces the strongest interfacial interaction and the best mechanical properties. In the presence of covalent bonds, however, the reinforcing effect is adversely affected due to the sp2-sp3 bond transformation which partially degrades graphene. The present work provides, for the first time, valuable insight into the role of substrate surface modification on the mechanical performance of Al/Gr nanocomposites.
Collapse
Affiliation(s)
- Jun Liu
- School of Engineering, RMIT University, Bundoora, VIC 3083, Australia
| | - Yingyan Zhang
- School of Engineering, RMIT University, Bundoora, VIC 3083, Australia
| | - Henin Zhang
- School of Engineering, RMIT University, Bundoora, VIC 3083, Australia
| | - Jie Yang
- School of Engineering, RMIT University, Bundoora, VIC 3083, Australia
| |
Collapse
|
13
|
Galbiati M, Persichetti L, Gori P, Pulci O, Bianchi M, Di Gaspare L, Tersoff J, Coletti C, Hofmann P, De Seta M, Camilli L. Tuning the Doping of Epitaxial Graphene on a Conventional Semiconductor via Substrate Surface Reconstruction. J Phys Chem Lett 2021; 12:1262-1267. [PMID: 33497236 DOI: 10.1021/acs.jpclett.0c03649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Combining scanning tunneling microscopy and angle-resolved photoemission spectroscopy, we demonstrate how to tune the doping of epitaxial graphene from p to n by exploiting the structural changes that occur spontaneously on the Ge surface upon thermal annealing. Furthermore, using first-principle calculations, we build a model that successfully reproduces the experimental observations. Since the ability to modify graphene electronic properties is of fundamental importance when it comes to applications, our results provide an important contribution toward the integration of graphene with conventional semiconductors.
Collapse
Affiliation(s)
- Miriam Galbiati
- Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | | | - Paola Gori
- Department of Engineering, Roma Tre University, 00146 Rome, Italy
| | - Olivia Pulci
- Department of Physics, University of Rome "Tor Vergata", 00133 Rome, Italy
- Istituto Nazionale di Fisica Nucleare, Roma 2, 00133 Rome, Italy
| | - Marco Bianchi
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | | | - Jerry Tersoff
- IBM Research Division, T.J. Watson Research Center, Yorktown Heights, New York, New York 10598, United States
| | - Camilla Coletti
- Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa 56127, Italy
- Graphene Laboratories, Istituto Italiano di Tecnologia, Genova 16163, Italy
| | - Philip Hofmann
- Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
| | - Monica De Seta
- Department of Sciences, Roma Tre University, 00146 Rome, Italy
| | - Luca Camilli
- Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
- Department of Physics, University of Rome "Tor Vergata", 00133 Rome, Italy
| |
Collapse
|
14
|
Barcelon JE, Smerieri M, Carraro G, Wojciechowski P, Vattuone L, Rocca M, Nappini S, Píš I, Magnano E, Bondino F, Vaghi L, Papagni A, Savio L. Morphological characterization and electronic properties of pristine and oxygen-exposed graphene nanoribbons on Ag(110). Phys Chem Chem Phys 2021; 23:7926-7937. [PMID: 33403374 DOI: 10.1039/d0cp04051g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Graphene nanoribbons (GNRs) are at the frontier of research on graphene materials since the 1D quantum confinement of electrons allows for the opening of an energy gap. GNRs of uniform and well-defined size and shape can be grown using the bottom-up approach, i.e. by surface assisted polymerization of aromatic hydrocarbons. Since the electronic properties of the nanostructures depend on their width and on their edge states, by careful choice of the precursor molecule it is possible to design GNRs with tailored properties. A key issue for their application in nanoelectronics is their stability under operative conditions. Here, we characterize pristine and oxygen-exposed 1.0 nm wide GNRs with a well-defined mixed edge-site sequence (two zig-zag and one armchair) synthesized on Ag(110) from 1,6-dibromo-pyrene precursors. The energy gap and the presence of quantum confined states are investigated by scanning tunneling spectroscopy. The effect of oxygen exposure under ultra-high vacuum conditions is inferred from scanning tunneling microscopy images and photoemission spectra. Our results demonstrate that oxygen exposure deeply affects the overall system by interacting both with the nanoribbons and with the substrate; this factor must be considered for supported GNRs under operative conditions.
Collapse
|
15
|
Ogawa S, Yamaguchi H, Holby EF, Yamada T, Yoshigoe A, Takakuwa Y. Gas Barrier Properties of Chemical Vapor-Deposited Graphene to Oxygen Imparted with Sub-electronvolt Kinetic Energy. J Phys Chem Lett 2020; 11:9159-9164. [PMID: 33100012 DOI: 10.1021/acs.jpclett.0c02112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Graphene gas-barrier performance holds great interest from both scientific and technological perspectives. Using in situ synchrotron X-ray photoelectron spectroscopy, we demonstrate that chemical vapor-deposited monolayer graphene loses its gas-barrier performance almost completely when oxygen molecules are imparted with sub-electronvolt kinetic energy but retains its gas-barrier performance when the molecules are not energized. The permeation process is nondestructive. Molecular dynamics-based simulation suggests kinetic energy-mediated chemical reactions catalyzed by common graphene defects as a responsible mechanism.
Collapse
Affiliation(s)
| | - Hisato Yamaguchi
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Edward F Holby
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Takatoshi Yamada
- National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8565, Japan
| | | | | |
Collapse
|
16
|
Azpeitia J, Palacio I, Martínez J, Muñoz-Ochando I, Lauwaet K, Mompean F, Ellis G, García-Hernández M, Martín-Gago J, Munuera C, López M. Oxygen intercalation in PVD graphene grown on copper substrates: A decoupling approach. APPLIED SURFACE SCIENCE 2020; 529:147100. [PMID: 33154607 PMCID: PMC7116314 DOI: 10.1016/j.apsusc.2020.147100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigate the intercalation process of oxygen in-between a PVD-grown graphene layer and different copper substrates as a methodology for reducing the substrate-layer interaction. This growth method leads to an extended defect-free graphene layer that strongly couples with the substrate. We have found, by means of X-ray photoelectron spectroscopy, that after oxygen exposure at different temperatures, ranging from 280 °C to 550 °C, oxygen intercalates at the interface of graphene grown on Cu foil at an optimal temperature of 500 °C. The low energy electron diffraction technique confirms the adsorption of an atomic oxygen adlayer on top of the Cu surface and below graphene after oxygen exposure at elevated temperature, but no oxidation of the substrate is induced. The emergence of the 2D Raman peak, quenched by the large interaction with the substrate, reveals that the intercalation process induces a structural undoing. As suggested by atomic force microscopy, the oxygen intercalation does not change significantly the surface morphology. Moreover, theoretical simulations provide further insights into the electronic and structural undoing process. This protocol opens the door to an efficient methodology to weaken the graphene-substrate interaction for a more efficient transfer to arbitrary surfaces.
Collapse
Affiliation(s)
- J. Azpeitia
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - I. Palacio
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - J.I. Martínez
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - I. Muñoz-Ochando
- Instituto de Ciencia y Tecnología de Polímeros, Consejo Superior de Investigaciones Científicas, ES-28006 Madrid, Spain
| | - K. Lauwaet
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - F.J. Mompean
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - G.J. Ellis
- Instituto de Ciencia y Tecnología de Polímeros, Consejo Superior de Investigaciones Científicas, ES-28006 Madrid, Spain
| | - M. García-Hernández
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - J.A. Martín-Gago
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - C. Munuera
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| | - M.F. López
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco ES-28049, Madrid, Spain
| |
Collapse
|
17
|
Braeuninger-Weimer P, Burton OJ, Zeller P, Amati M, Gregoratti L, Weatherup RS, Hofmann S. Crystal Orientation Dependent Oxidation Modes at the Buried Graphene-Cu Interface. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2020; 32:7766-7776. [PMID: 32982043 PMCID: PMC7513576 DOI: 10.1021/acs.chemmater.0c02296] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/25/2020] [Indexed: 06/11/2023]
Abstract
We combine spatially resolved scanning photoelectron spectroscopy with confocal Raman and optical microscopy to reveal how the oxidation of the buried graphene-Cu interface relates to the Cu crystallographic orientation. We analyze over 100 different graphene covered Cu (high and low index) orientations exposed to air for 2 years. Four general oxidation modes are observed that can be mapped as regions onto the polar plot of Cu surface orientations. These modes are (1) complete, (2) irregular, (3) inhibited, and (4) enhanced wrinkle interface oxidation. We present a comprehensive characterization of these modes, consider the underlying mechanisms, compare air and water mediated oxidation, and discuss this in the context of the diverse prior literature in this area. This understanding incorporates effects from across the wide parameter space of 2D material interface engineering, relevant to key challenges in their emerging applications, ranging from scalable transfer to electronic contacts, encapsulation, and corrosion protection.
Collapse
Affiliation(s)
| | - Oliver J. Burton
- Department
of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | - Patrick Zeller
- Elettra-Sincrotrone
Trieste S.C.p.A., AREA Science Park, S.S. 14 km 163.5, 34149 Trieste, Italy
| | - Matteo Amati
- Elettra-Sincrotrone
Trieste S.C.p.A., AREA Science Park, S.S. 14 km 163.5, 34149 Trieste, Italy
| | - Luca Gregoratti
- Elettra-Sincrotrone
Trieste S.C.p.A., AREA Science Park, S.S. 14 km 163.5, 34149 Trieste, Italy
| | - Robert S. Weatherup
- Department
of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United
Kingdom
| | - Stephan Hofmann
- Department
of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| |
Collapse
|
18
|
Liu Y, Liu C, Wang J, Gao Q, Hu Z, Hao W, Xu X, Du Y, Zhuang J. Reversible Potassium Intercalation in Blue Phosphorene-Au Network Driven by an Electric Field. J Phys Chem Lett 2020; 11:5584-5590. [PMID: 32584041 DOI: 10.1021/acs.jpclett.0c01835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Foreign atom intercalation into an interface alters the strength of interlayer interaction and leads to the novel types of desirable properties. Here, we report an investigation via scanning tunnelling microscopy (STM) and scanning tunnelling spectroscopy (STS) of reversible potassium (K) intercalation in the blue phosphorene (blueP)-Au network that can be locally induced by an external electric field. The unique structure of the blueP-Au network provides large space in its pores for the intercalation and deintercalation process. The X-ray photoemission spectroscopy results reveal that the intercalated K atoms are bonded with Au atoms in substrate, which weakens the interaction between the blueP-Au network and Au(111). The STS and angle-resolved photoemission spectroscopy results indicate that the electronic properties of the blueP-Au network have been modulated after the K intercalation. Such reversible intercalation and deintercalation transitions in the blueP-Au network are relevant for the design of the nanoelectronic devices as well as for its application in K-ion batteries.
Collapse
Affiliation(s)
- Yani Liu
- BUAA-UOW Joint Centre, School of Physics, Beihang University, Haidian District, Beijing 100091, China
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW 2525, Australia
| | - Chen Liu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Jiaou Wang
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Qian Gao
- School of Physics, Nankai University, Tianjin 300071, China
| | - Zhenpeng Hu
- School of Physics, Nankai University, Tianjin 300071, China
| | - Weichang Hao
- BUAA-UOW Joint Centre, School of Physics, Beihang University, Haidian District, Beijing 100091, China
| | - Xun Xu
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW 2525, Australia
| | - Yi Du
- BUAA-UOW Joint Centre, School of Physics, Beihang University, Haidian District, Beijing 100091, China
- Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong, Wollongong, NSW 2525, Australia
| | - Jincheng Zhuang
- BUAA-UOW Joint Centre, School of Physics, Beihang University, Haidian District, Beijing 100091, China
| |
Collapse
|
19
|
Armano A, Buscarino G, Messina F, Sciortino A, Cannas M, Gelardi FM, Giannazzo F, Schilirò E, Agnello S. Dynamic Modification of Fermi Energy in Single-Layer Graphene by Photoinduced Electron Transfer from Carbon Dots. NANOMATERIALS 2020; 10:nano10030528. [PMID: 32183471 PMCID: PMC7153610 DOI: 10.3390/nano10030528] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/06/2020] [Accepted: 03/11/2020] [Indexed: 12/20/2022]
Abstract
Graphene (Gr)—a single layer of two-dimensional sp2 carbon atoms—and Carbon Dots (CDs)—a novel class of carbon nanoparticles—are two outstanding nanomaterials, renowned for their peculiar properties: Gr for its excellent charge-transport, and CDs for their impressive emission properties. Such features, coupled with a strong sensitivity to the environment, originate the interest in bringing together these two nanomaterials in order to combine their complementary properties. In this work, the investigation of a solid-phase composite of CDs deposited on Gr is reported. The CD emission efficiency is reduced by the contact of Gr. At the same time, the Raman analysis of Gr demonstrates the increase of Fermi energy when it is in contact with CDs under certain conditions. The interaction between CDs and Gr is modeled in terms of an electron-transfer from photoexcited CDs to Gr, wherein an electron is first transferred from the carbon core to the surface states of CDs, and from there to Gr. There, the accumulated electrons determine a dynamical n-doping effect modulated by photoexcitation. The CD–graphene interaction unveiled herein is a step forward in the understanding of the mutual influence between carbon-based nanomaterials, with potential prospects in light conversion applications.
Collapse
Affiliation(s)
- Angelo Armano
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
- Dipartimento di Fisica e Astronomia-Ettore Majorana, Università degli Studi di Catania, Via Santa Sofia 64, 95123 Catania, Italy
| | - Gianpiero Buscarino
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
- ATeN Center, Università degli Studi di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
- Consiglio Nazionale delle Ricerche-Istituto per la Microelettronica e Microsistemi, Strada VIII 5, 95121 Catania, Italy; (F.G.); (E.S.)
| | - Fabrizio Messina
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
- ATeN Center, Università degli Studi di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
| | - Alice Sciortino
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
| | - Marco Cannas
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
| | - Franco Mario Gelardi
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
| | - Filippo Giannazzo
- Consiglio Nazionale delle Ricerche-Istituto per la Microelettronica e Microsistemi, Strada VIII 5, 95121 Catania, Italy; (F.G.); (E.S.)
| | - Emanuela Schilirò
- Consiglio Nazionale delle Ricerche-Istituto per la Microelettronica e Microsistemi, Strada VIII 5, 95121 Catania, Italy; (F.G.); (E.S.)
| | - Simonpietro Agnello
- Dipartimento di Fisica e Chimica-Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, 90123 Palermo, Italy; (A.A.); (G.B.); (F.M.); (A.S.); (M.C.); (F.M.G.)
- ATeN Center, Università degli Studi di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy
- Consiglio Nazionale delle Ricerche-Istituto per la Microelettronica e Microsistemi, Strada VIII 5, 95121 Catania, Italy; (F.G.); (E.S.)
- Correspondence:
| |
Collapse
|
20
|
Bisbo MK, Hammer B. Efficient Global Structure Optimization with a Machine-Learned Surrogate Model. PHYSICAL REVIEW LETTERS 2020; 124:086102. [PMID: 32167316 DOI: 10.1103/physrevlett.124.086102] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/20/2019] [Accepted: 01/23/2020] [Indexed: 05/18/2023]
Abstract
We propose a scheme for global optimization with first-principles energy expressions of atomistic structure. While unfolding its search, the method actively learns a surrogate model of the potential energy landscape on which it performs a number of local relaxations (exploitation) and further structural searches (exploration). Assuming Gaussian processes, deploying two separate kernel widths to better capture rough features of the energy landscape while retaining a good resolution of local minima, an acquisition function is used to decide on which of the resulting structures is the more promising and should be treated at the first-principles level. The method is demonstrated to outperform by 2 orders of magnitude a well established first-principles based evolutionary algorithm in finding surface reconstructions. Finally, global optimization with first-principles energy expressions is utilized to identify initial stages of the edge oxidation and oxygen intercalation of graphene sheets on the Ir(111) surface.
Collapse
Affiliation(s)
- Malthe K Bisbo
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Bjørk Hammer
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| |
Collapse
|
21
|
Apostol NG, Lizzit D, Lungu GA, Lacovig P, Chirilă CF, Pintilie L, Lizzit S, Teodorescu CM. Resistance hysteresis correlated with synchrotron radiation surface studies in atomic sp2 layers of carbon synthesized on ferroelectric (001) lead zirconate titanate in an ultrahigh vacuum. RSC Adv 2020; 10:1522-1534. [PMID: 35494695 PMCID: PMC9047335 DOI: 10.1039/c9ra09131a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 12/31/2019] [Indexed: 12/29/2022] Open
Abstract
Graphene-like layers synthesized in ultrahigh vacuum, characterized by surface science techniques, exhibit resistance hysteresis depending on the carbon coverage.
Collapse
|
22
|
Scardamaglia M, Struzzi C, Zakharov A, Reckinger N, Zeller P, Amati M, Gregoratti L. Highlighting the Dynamics of Graphene Protection toward the Oxidation of Copper Under Operando Conditions. ACS APPLIED MATERIALS & INTERFACES 2019; 11:29448-29457. [PMID: 31328499 DOI: 10.1021/acsami.9b08918] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We performed spatially resolved near-ambient-pressure photoemission spectromicroscopy on graphene-coated copper in operando under oxidation conditions in an oxygen atmosphere (0.1 mbar). We investigated regions with bare copper and areas covered with mono- and bi-layer graphene flakes, in isobaric and isothermal experiments. The key method in this work is the combination of spatial and chemical resolution of the scanning photoemission microscope operating in a near-ambient-pressure environment, thus allowing us to overcome both the material and pressure gap typical of standard ultrahigh-vacuum X-ray photoelectron spectroscopy (XPS) and to observe in operando the protection mechanism of graphene toward copper oxidation. The ability to perform spatially resolved XPS and imaging at high pressure allows for the first time a unique characterization of the oxidation phenomenon by means of photoelectron spectromicroscopy, pushing the limits of this technique from fundamental studies to real materials under working conditions. Although bare Cu oxidizes naturally at room temperature, our results demonstrate that such a graphene coating acts as an effective barrier to prevent copper oxidation at high temperatures (over 300 °C), until oxygen intercalation beneath graphene starts from boundaries and defects. We also show that bilayer flakes can protect at even higher temperatures. The protected metallic substrate, therefore, does not suffer corrosion, preserving its metallic characteristic, making this coating appealing for any application in an aggressive atmospheric environment at high temperatures.
Collapse
Affiliation(s)
- Mattia Scardamaglia
- ChIPS, University of Mons , 7000 Mons , Belgium
- MAX IV Laboratory , University of Lund , 22100 Lund , Sweden
| | - Claudia Struzzi
- MAX IV Laboratory , University of Lund , 22100 Lund , Sweden
| | - Alexei Zakharov
- MAX IV Laboratory , University of Lund , 22100 Lund , Sweden
| | | | - Patrick Zeller
- Elettra-Sincrotrone Trieste S.C.p.A. , 34149 Trieste , Italy
| | - Matteo Amati
- Elettra-Sincrotrone Trieste S.C.p.A. , 34149 Trieste , Italy
| | - Luca Gregoratti
- Elettra-Sincrotrone Trieste S.C.p.A. , 34149 Trieste , Italy
| |
Collapse
|
23
|
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.
Collapse
Affiliation(s)
- Richard Balog
- Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Ma D, Fu Z, Sui X, Bai K, Qiao J, Yan C, Zhang Y, Hu J, Xiao Q, Mao X, Duan W, He L. Modulating the Electronic Properties of Graphene by Self-Organized Sulfur Identical Nanoclusters and Atomic Superlattices Confined at an Interface. ACS NANO 2018; 12:10984-10991. [PMID: 30252446 DOI: 10.1021/acsnano.8b04874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Ordered atomic-scale superlattices on a surface hold great interest both for basic science and for potential applications in advanced technology. However, controlled fabrication of superlattices down to the atomic scale has proven exceptionally challenging. Here we develop a segregation method to realize self-organization of S superlattices at the interface of graphene and S-rich Cu substrates. Via scanning tunneling microscope measurements, we directly image well-ordered identical nanocluster superlattices and atomic superlattices under the cover of graphene. Scanning tunneling spectra show that the superlattices in turn could modulate the electronic structure of top-layer graphene. Importantly, a special-ordered S monatomic superlattice commensurate with a graphene lattice is found to drive semimetal graphene into a symmetry-broken phase-the electronic Kekulé distortion phase-which opens a bandgap of ∼245 meV.
Collapse
Affiliation(s)
- Donglin Ma
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
- Department of Physics , Capital Normal University , Beijing , 100048 , People's Republic of China
| | - Zhongqiu Fu
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Xuelei Sui
- State Key Laboratory of Low-Dimensional Quantum Physics and Collaborative Innovation Center of Quantum Matter, Department of Physics , Tsinghua University , Beijing , 100084 , People's Republic of China
| | - Keke Bai
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Jiabin Qiao
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Chao Yan
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Yu Zhang
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Jingyi Hu
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Qian Xiao
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Xinrui Mao
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| | - Wenhui Duan
- State Key Laboratory of Low-Dimensional Quantum Physics and Collaborative Innovation Center of Quantum Matter, Department of Physics , Tsinghua University , Beijing , 100084 , People's Republic of China
| | - Lin He
- Center for Advanced Quantum Studies, Department of Physics , Beijing Normal University , Beijing , 100875 , People's Republic of China
| |
Collapse
|
25
|
Cattelan M, Fox NA. A Perspective on the Application of Spatially Resolved ARPES for 2D Materials. NANOMATERIALS (BASEL, SWITZERLAND) 2018; 8:E284. [PMID: 29702567 PMCID: PMC5977298 DOI: 10.3390/nano8050284] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 04/20/2018] [Accepted: 04/23/2018] [Indexed: 12/13/2022]
Abstract
In this paper, a perspective on the application of Spatially- and Angle-Resolved PhotoEmission Spectroscopy (ARPES) for the study of two-dimensional (2D) materials is presented. ARPES allows the direct measurement of the electronic band structure of materials generating extremely useful insights into their electronic properties. The possibility to apply this technique to 2D materials is of paramount importance because these ultrathin layers are considered fundamental for future electronic, photonic and spintronic devices. In this review an overview of the technical aspects of spatially localized ARPES is given along with a description of the most advanced setups for laboratory and synchrotron-based equipment. This technique is sensitive to the lateral dimensions of the sample. Therefore, a discussion on the preparation methods of 2D material is presented. Some of the most interesting results obtained by ARPES are reported in three sections including: graphene, transition metal dichalcogenides (TMDCs) and 2D heterostructures. Graphene has played a key role in ARPES studies because it inspired the use of this technique with other 2D materials. TMDCs are presented for their peculiar transport, optical and spin properties. Finally, the section featuring heterostructures highlights a future direction for research into 2D material structures.
Collapse
Affiliation(s)
- Mattia Cattelan
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8 1TS, UK; .
| | - Neil A Fox
- School of Chemistry, University of Bristol, Cantocks Close, Bristol BS8 1TS, UK; .
- H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
| |
Collapse
|
26
|
Palacio I, Otero-Irurueta G, Alonso C, Martínez JI, López-Elvira E, Muñoz-Ochando I, Salavagione HJ, López MF, García-Hernández M, Méndez J, Ellis GJ, Martín-Gago JA. Chemistry below graphene: decoupling epitaxial graphene from metals by potential-controlled electrochemical oxidation. CARBON 2018; 129:837-846. [PMID: 30190626 PMCID: PMC6120681 DOI: 10.1016/j.carbon.2017.12.104] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
While high-quality defect-free epitaxial graphene can be efficiently grown on metal substrates, strong interaction with the supporting metal quenches its outstanding properties. Thus, protocols to transfer graphene to insulating substrates are obligatory, and these often severely impair graphene properties by the introduction of structural or chemical defects. Here we describe a simple and easily scalable general methodology to structurally and electronically decouple epitaxial graphene from Pt(111) and Ir(111) metal surfaces. A multi-technique characterization combined with ab-initio calculations was employed to fully explain the different steps involved in the process. It was shown that, after a controlled electrochemical oxidation process, a single-atom thick metal-hydroxide layer intercalates below graphene, decoupling it from the metal substrate. This decoupling process occurs without disrupting the morphology and electronic properties of graphene. The results suggest that suitably optimized electrochemical treatments may provide effective alternatives to current transfer protocols for graphene and other 2D materials on diverse metal surfaces.
Collapse
Affiliation(s)
- Irene Palacio
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Gonzalo Otero-Irurueta
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
- Centre for Mechanical Technology and Automation (TEMA), Dept. Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Concepción Alonso
- Dept. Applied Physical Chemistry, Autonomous University of Madrid, 28049 Madrid, Spain
| | - José I. Martínez
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Elena López-Elvira
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Isabel Muñoz-Ochando
- Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
| | - Horacio J. Salavagione
- Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
| | - María F. López
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Mar García-Hernández
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Javier Méndez
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Gary J. Ellis
- Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
| | - José A. Martín-Gago
- Materials Science Factory, Dept. Surfaces, Coatings and Molecular Astrophysics, Institute of Material Science of Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| |
Collapse
|
27
|
Simon S, Voloshina E, Tesch J, Förschner F, Enenkel V, Herbig C, Knispel T, Tries A, Kröger J, Dedkov Y, Fonin M. Layer-by-Layer Decoupling of Twisted Graphene Sheets Epitaxially Grown on a Metal Substrate. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1703701. [PMID: 29450969 DOI: 10.1002/smll.201703701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/23/2017] [Indexed: 06/08/2023]
Abstract
The electronic properties of graphene can be efficiently altered upon interaction with the underlying substrate resulting in a dramatic change of charge carrier behavior. Here, the evolution of the local electronic properties of epitaxial graphene on a metal upon the controlled formation of multilayers, which are produced by intercalation of atomic carbon in graphene/Ir(111), is investigated. Using scanning tunneling microscopy and Landau-level spectroscopy, it is shown that for a monolayer and bilayers with small-angle rotations, Landau levels are fully suppressed, indicating that the metal-graphene interaction is largely confined to the first graphene layer. Bilayers with large twist angles as well as twisted trilayers demonstrate a sequence of pronounced Landau levels characteristic for a free-standing graphene monolayer pointing toward an effective decoupling of the top layer from the metal substrate. These findings give evidence for the controlled preparation of epitaxial graphene multilayers with a different degree of decoupling, which represent an ideal platform for future electronic and spintronic applications.
Collapse
Affiliation(s)
- Sabina Simon
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - Elena Voloshina
- Physics Department, Shanghai University, Shanghai, 200444, China
| | - Julia Tesch
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - Felix Förschner
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - Vivien Enenkel
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - Charlotte Herbig
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
- Department of Physics, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Timo Knispel
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937, Köln, Germany
| | - Alexander Tries
- Institut für Physik, Technische Universität Ilmenau, 98693, Ilmenau, Germany
| | - Jörg Kröger
- Institut für Physik, Technische Universität Ilmenau, 98693, Ilmenau, Germany
| | - Yuriy Dedkov
- Physics Department, Shanghai University, Shanghai, 200444, China
| | - Mikhail Fonin
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| |
Collapse
|
28
|
Romero-Muñiz C, Martín-Recio A, Pou P, Gómez-Rodríguez JM, Pérez R. Unveiling the atomistic mechanisms for oxygen intercalation in a strongly interacting graphene–metal interface. Phys Chem Chem Phys 2018; 20:13370-13378. [PMID: 29721570 DOI: 10.1039/c8cp01032c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The atomistic mechanisms involved in the oxygen intercalation in the strongly interacting G/Rh(111) system are characterized in a comprehensive experimental and theoretical study, combining scanning tunneling microscopy and DFT calculations.
Collapse
Affiliation(s)
- Carlos Romero-Muñiz
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid
- E-28049 Madrid
- Spain
| | - Ana Martín-Recio
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid
- E-28049 Madrid
- Spain
| | - Pablo Pou
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid
- E-28049 Madrid
- Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid
- E-28049 Madrid
| | - José M. Gómez-Rodríguez
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid
- E-28049 Madrid
- Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid
- E-28049 Madrid
| | - Rubén Pérez
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid
- E-28049 Madrid
- Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid
- E-28049 Madrid
| |
Collapse
|
29
|
Miniussi E, Bernard C, Cun HY, Probst B, Leuenberger D, Mette G, Zabka WD, Weinl M, Haluska M, Schreck M, Osterwalder J, Greber T. Fermi surface map of large-scale single-orientation graphene on SiO 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:475001. [PMID: 28949299 DOI: 10.1088/1361-648x/aa8f27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Large scale tetraoctylammonium-assisted electrochemical transfer of graphene grown on single-crystalline Ir(1 1 1) films by chemical vapour deposition is reported. The transferred samples are characterized in air with optical microscopy, Raman spectroscopy and four point transport measurements, providing the sheet resistance and the Hall carrier concentration. In vacuum we apply low energy electron diffraction and photoelectron spectroscopy that indicate transferred large-scale single orientation graphene. Angular resolved photoemission reveals a Fermi surface and a Dirac point energy which are consistent with charge neutral graphene.
Collapse
Affiliation(s)
- E Miniussi
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Wang S, Feng Y, Yu M, Wan Q, Lin S. Confined Catalysis in the g-C 3N 4/Pt(111) Interface: Feasible Molecule Intercalation, Tunable Molecule-Metal Interaction, and Enhanced Reaction Activity of CO Oxidation. ACS APPLIED MATERIALS & INTERFACES 2017; 9:33267-33273. [PMID: 28876886 DOI: 10.1021/acsami.7b08665] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The deposition of a two-dimensional (2D) atomic nanosheet on a metal surface has been considered as a new route for tuning the molecule-metal interaction and surface reactivity in terms of the confinement effect. In this work, we use first-principles calculations to systematically explore a novel nanospace constructed by placing a 2D graphitic carbon nitride (g-C3N4) nanosheet over a Pt(111) surface. The confined catalytic activity in this nanospace is investigated using CO oxidation as a model reaction. With the inherent triangular pores in the g-C3N4 overlayer being taken advantage of, molecules such as CO and O2 can diffuse to adsorb on the Pt(111) surface underneath the g-C3N4 overlayer. Moreover, the mechanism of intercalation is also elucidated, and the results reveal that the energy barrier depends mainly on the properties of the molecule and the channel. Importantly, the molecule-catalyst interaction can be tuned by the g-C3N4 overlayer, considerably reducing the adsorption energy of CO on Pt(111) and leading to enhanced reactivity in CO oxidation. This work will provide important insight for constructing a promising nanoreactor in which the following is observed: The molecule intercalation is facile; the molecule-metal interaction is efficiently tuned; the metal-catalyzed reaction is promoted.
Collapse
Affiliation(s)
- Shujiao Wang
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University , Fuzhou 350002, China
| | - Yingxin Feng
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University , Fuzhou 350002, China
| | - Ming'an Yu
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University , Fuzhou 350002, China
| | - Qiang Wan
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University , Fuzhou 350002, China
| | - Sen Lin
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University , Fuzhou 350002, China
| |
Collapse
|
31
|
Spectroscopic observation of oxygen dissociation on nitrogen-doped graphene. Sci Rep 2017; 7:7960. [PMID: 28801640 PMCID: PMC5554215 DOI: 10.1038/s41598-017-08651-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 07/17/2017] [Indexed: 12/03/2022] Open
Abstract
Carbon nanomaterials’ reactivity towards oxygen is very poor, limiting their potential applications. However, nitrogen doping is an established way to introduce active sites that facilitate interaction with gases. This boosts the materials’ reactivity for bio-/gas sensing and enhances their catalytic performance for the oxygen reduction reaction. Despite this interest, the role of differently bonded nitrogen dopants in the interaction with oxygen is obscured by experimental challenges and has so far resisted clear conclusions. We study the interaction of molecular oxygen with graphene doped via nitrogen plasma by in situ high-resolution synchrotron techniques, supported by density functional theory core level simulations. The interaction leads to oxygen dissociation and the formation of carbon-oxygen single bonds on graphene, along with a band gap opening and a rounding of the Dirac cone. The change of the N 1 s core level signal indicates that graphitic nitrogen is involved in the observed mechanism: the adsorbed oxygen molecule is dissociated and the two O atoms chemisorb with epoxy bonds to the nearest carbon neighbours of the graphitic nitrogen. Our findings help resolve existing controversies and offer compelling new evidence of the ORR pathway.
Collapse
|
32
|
Gao L, Wang Y, Li H, Li Q, Ta N, Zhuang L, Fu Q, Bao X. A nickel nanocatalyst within a h-BN shell for enhanced hydrogen oxidation reactions. Chem Sci 2017; 8:5728-5734. [PMID: 28989613 PMCID: PMC5621155 DOI: 10.1039/c7sc01615h] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/09/2017] [Indexed: 12/04/2022] Open
Abstract
The confinement effect of h-BN shells helps to maintain active metallic Ni cores and strengthen the HOR processes occurring at h-BN/Ni interfaces.
The development of low-cost and high-performance electrocatalysts remains a challenge for the hydrogen oxidation reaction (HOR) in alkaline membrane fuel cells. Here, we have reported novel Ni@h-BN core–shell nanocatalysts consisting of nickel nanoparticles encapsulated in few-layer h-BN shells. The Ni@h-BN catalysts exhibit an improved HOR performance compared with the bare Ni nanoparticles. In situ characterization experiments and density functional theory calculations indicate that the interactions of the O, H, and OH species with the Ni surface under the h-BN shell are weakened, which helps to maintain the active metallic Ni phase both in air and in the electrolyte and strengthen the HOR processes occurring at the h-BN/Ni interfaces. These results suggest a new route for designing high-performance non-noble metal electrocatalysts with encapsulating two-dimensional material overlayers for HOR reactions.
Collapse
Affiliation(s)
- Lijun Gao
- State Key Laboratory of Catalysis , iChEM , Dalian Institute of Chemical Physics , The Chinese Academy of Sciences , Dalian 116023 , P. R. China . .,Department of Chemical Physics , University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Ying Wang
- College of Chemistry and Molecular Sciences , Hubei Key Lab of Electrochemical Power Sources , Institute for Advanced Studies , Wuhan University , Wuhan 430072 , P. R. China .
| | - Haobo Li
- State Key Laboratory of Catalysis , iChEM , Dalian Institute of Chemical Physics , The Chinese Academy of Sciences , Dalian 116023 , P. R. China .
| | - Qihao Li
- College of Chemistry and Molecular Sciences , Hubei Key Lab of Electrochemical Power Sources , Institute for Advanced Studies , Wuhan University , Wuhan 430072 , P. R. China .
| | - Na Ta
- State Key Laboratory of Catalysis , iChEM , Dalian Institute of Chemical Physics , The Chinese Academy of Sciences , Dalian 116023 , P. R. China .
| | - Lin Zhuang
- College of Chemistry and Molecular Sciences , Hubei Key Lab of Electrochemical Power Sources , Institute for Advanced Studies , Wuhan University , Wuhan 430072 , P. R. China .
| | - Qiang Fu
- State Key Laboratory of Catalysis , iChEM , Dalian Institute of Chemical Physics , The Chinese Academy of Sciences , Dalian 116023 , P. R. China .
| | - Xinhe Bao
- State Key Laboratory of Catalysis , iChEM , Dalian Institute of Chemical Physics , The Chinese Academy of Sciences , Dalian 116023 , P. R. China .
| |
Collapse
|
33
|
Lee W, Kihm KD, Kim HG, Shin S, Lee C, Park JS, Cheon S, Kwon OM, Lim G, Lee W. In-Plane Thermal Conductivity of Polycrystalline Chemical Vapor Deposition Graphene with Controlled Grain Sizes. NANO LETTERS 2017; 17:2361-2366. [PMID: 28252971 DOI: 10.1021/acs.nanolett.6b05269] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Manipulation of the chemical vapor deposition graphene synthesis conditions, such as operating P, T, heating/cooling time intervals, and precursor gas concentration ratios (CH4/H2), allowed for synthesis of polycrystalline single-layered graphene with controlled grain sizes. The graphene samples were then suspended on 8 μm diameter patterned holes on a silicon-nitride (Si3N4) substrate, and the in-plane thermal conductivities k(T) for 320 K < T < 510 K were measured to be 2660-1230, 1890-1020, and 680-340 W/m·K for average grain sizes of 4.1, 2.2, and 0.5 μm, respectively, using an opto-thermal Raman technique. Fitting of these data by a simple linear chain model of polycrystalline thermal transport determined k = 5500-1980 W/m·K for single-crystal graphene for the same temperature range above; thus, significant reduction of k was achieved when the grain size was decreased from infinite down to 0.5 μm. Furthermore, detailed elaborations were performed to assess the measurement reliability of k by addressing the hole-edge boundary condition, and the air-convection/radiation losses from the graphene surface.
Collapse
Affiliation(s)
- Woomin Lee
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| | - Kenneth David Kihm
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
- Mechanical, Aerospace, and Biomedical Engineering, The University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Hong Goo Kim
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| | - Seungha Shin
- Mechanical, Aerospace, and Biomedical Engineering, The University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Changhyuk Lee
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| | - Jae Sung Park
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| | - Sosan Cheon
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| | - Oh Myoung Kwon
- Department of Mechanical Engineering, Korea University , Seoul 136-713, Republic of Korea
| | - Gyumin Lim
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| | - Woorim Lee
- School of Mechanical and Aerospace Engineering, Seoul National University , Seoul 151-744, Republic of Korea
| |
Collapse
|
34
|
Intercalation-etching of graphene on Pt(111) in H2 and O2 observed by in-situ low energy electron microscopy. Sci China Chem 2017. [DOI: 10.1007/s11426-017-9020-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
35
|
Trotochaud L, Head AR, Karslıoğlu O, Kyhl L, Bluhm H. Ambient pressure photoelectron spectroscopy: Practical considerations and experimental frontiers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:053002. [PMID: 27911885 DOI: 10.1088/1361-648x/29/5/053002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Over the past several decades, ambient pressure x-ray photoelectron spectroscopy (APXPS) has emerged as a powerful technique for in situ and operando investigations of chemical reactions under relevant ambient atmospheres far from ultra-high vacuum conditions. This review focuses on exemplary cases of APXPS experiments, giving special consideration to experimental techniques, challenges, and limitations specific to distinct condensed matter interfaces. We discuss APXPS experiments on solid/vapor interfaces, including the special case of 2D films of graphene and hexagonal boron nitride on metal substrates with intercalated gas molecules, liquid/vapor interfaces, and liquid/solid interfaces, which are a relatively new class of interfaces being probed by APXPS. We also provide a critical evaluation of the persistent limitations and challenges of APXPS, as well as the current experimental frontiers.
Collapse
Affiliation(s)
- Lena Trotochaud
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | | | | | | | | |
Collapse
|
36
|
Fu Q, Bao X. Surface chemistry and catalysis confined under two-dimensional materials. Chem Soc Rev 2017; 46:1842-1874. [DOI: 10.1039/c6cs00424e] [Citation(s) in RCA: 292] [Impact Index Per Article: 41.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Interfaces between 2D material overlayers and solid surfaces provide confined spaces for chemical processes, which have stimulated new chemistry under a 2D cover.
Collapse
Affiliation(s)
- Qiang Fu
- State Key Laboratory of Catalysis
- iChEM
- Dalian Institute of Chemical Physics, the Chinese Academy of Sciences
- Dalian 116023
- P. R. China
| | - Xinhe Bao
- State Key Laboratory of Catalysis
- iChEM
- Dalian Institute of Chemical Physics, the Chinese Academy of Sciences
- Dalian 116023
- P. R. China
| |
Collapse
|
37
|
Papp C. From Flat Surfaces to Nanoparticles: In Situ Studies of the Reactivity of Model Catalysts. Catal Letters 2016. [DOI: 10.1007/s10562-016-1925-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
38
|
Salmi Z, Koefoed L, Jensen BBE, Čabo AG, Hofmann P, Pedersen SU, Daasbjerg K. Electroinduced Intercalation of Tetraalkylammonium Ions at the Interface of Graphene Grown on Copper, Platinum, and Iridium. ChemElectroChem 2016. [DOI: 10.1002/celc.201600424] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Zakaria Salmi
- Carbon Dioxide Activation Center; Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO); Aarhus University; Langelandsgade 140 DK-8000 Aarhus C Denmark
| | - Line Koefoed
- Carbon Dioxide Activation Center; Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO); Aarhus University; Langelandsgade 140 DK-8000 Aarhus C Denmark
| | - Bjarke B. E. Jensen
- Carbon Dioxide Activation Center; Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO); Aarhus University; Langelandsgade 140 DK-8000 Aarhus C Denmark
- Newtec Engineering A/S; Staermosegårdsvej 18 DK-5230 Odense M Denmark
| | - Antonija Grubišić Čabo
- Department of Physics and Astronomy and iNANO Center; Aarhus University; Ny Munkegade 120 DK-8000 Aarhus C Denmark
| | - Philip Hofmann
- Department of Physics and Astronomy and iNANO Center; Aarhus University; Ny Munkegade 120 DK-8000 Aarhus C Denmark
| | - Steen U. Pedersen
- Carbon Dioxide Activation Center; Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO); Aarhus University; Langelandsgade 140 DK-8000 Aarhus C Denmark
| | - Kim Daasbjerg
- Carbon Dioxide Activation Center; Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO); Aarhus University; Langelandsgade 140 DK-8000 Aarhus C Denmark
| |
Collapse
|
39
|
Weatherup RS, Eren B, Hao Y, Bluhm H, Salmeron MB. Graphene Membranes for Atmospheric Pressure Photoelectron Spectroscopy. J Phys Chem Lett 2016; 7:1622-1627. [PMID: 27082434 DOI: 10.1021/acs.jpclett.6b00640] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Atmospheric pressure X-ray photoelectron spectroscopy (XPS) is demonstrated using single-layer graphene membranes as photoelectron-transparent barriers that sustain pressure differences in excess of 6 orders of magnitude. The graphene serves as a support for catalyst nanoparticles under atmospheric pressure reaction conditions (up to 1.5 bar), where XPS allows the oxidation state of Cu nanoparticles and gas phase species to be simultaneously probed. We thereby observe that the Cu(2+) oxidation state is stable in O2 (1 bar) but is spontaneously reduced under vacuum. We further demonstrate the detection of various gas-phase species (Ar, CO, CO2, N2, O2) in the pressure range 10-1500 mbar including species with low photoionization cross sections (He, H2). Pressure-dependent changes in the apparent binding energies of gas-phase species are observed, attributable to changes in work function of the metal-coated grids supporting the graphene. We expect atmospheric pressure XPS based on this graphene membrane approach to be a valuable tool for studying nanoparticle catalysis.
Collapse
Affiliation(s)
| | | | | | | | - Miquel B Salmeron
- Department of Materials Science and Engineering, University of California , Berkeley, California 94720-1760, United States
| |
Collapse
|
40
|
Restoring a nearly free-standing character of graphene on Ru(0001) by oxygen intercalation. Sci Rep 2016; 6:20285. [PMID: 26852734 PMCID: PMC4745051 DOI: 10.1038/srep20285] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 12/30/2015] [Indexed: 11/26/2022] Open
Abstract
Realization of a free-standing graphene is always a demanding task. Here we use scanning probe microscopy and spectroscopy to study the crystallographic structure and electronic properties of the uniform nearly free-standing graphene layers obtained by intercalation of oxygen monolayer in the “strongly” bonded graphene/Ru(0001) interface. Spectroscopic data show that such graphene layer is heavily p-doped with the Dirac point located at 552 meV above the Fermi level. Experimental data are understood within density-functional theory approach and the observed effects are in good agreement with the theoretical data.
Collapse
|
41
|
Martínez-Galera AJ, Schröder UA, Huttmann F, Jolie W, Craes F, Busse C, Caciuc V, Atodiresei N, Blügel S, Michely T. Oxygen orders differently under graphene: new superstructures on Ir(111). NANOSCALE 2016; 8:1932-1943. [PMID: 26426949 DOI: 10.1039/c5nr04976h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Using scanning tunneling microscopy, the oxygen adsorbate superstructures on bare Ir(111) are identified and compared to the ones formed by intercalation in between graphene and the Ir(111) substrate. For bare Ir(111) we observe O-(2 × 2) and O-(2 × 1) structures, thereby clarifying a persistent uncertainty about the existence of these structures and the role of defects for their stability. For the case of graphene-covered Ir(111), oxygen intercalation superstructures can be imaged through the graphene monolayer by choosing proper tunneling conditions. Depending on the pressure, temperature and duration of O2 exposure as well as on the graphene morphology, O-(2 × 2), O-(√3×√3)-R30°, O-(2 × 1) and O-(2√3 × 2√3)-R30° superstructures with respect to Ir(111) are observed under the graphene cover. Two of these structures, the O-(√3 × √3)-R30° and the (2√3 × 2√3)-R30° structure are only observed when the graphene layer is on top. Phase coexistence and formation conditions of the intercalation structures between graphene and Ir(111) are analyzed. The experimental results are compared to density functional theory calculations including dispersive forces. The existence of these phases under graphene and their absence on bare Ir(111) are discussed in terms of possible changes in the adsorbate-substrate interaction due to the presence of the graphene cover.
Collapse
Affiliation(s)
| | - U A Schröder
- II. Physikalisches Institut, Universität zu Köln, Germany.
| | - F Huttmann
- II. Physikalisches Institut, Universität zu Köln, Germany.
| | - W Jolie
- II. Physikalisches Institut, Universität zu Köln, Germany.
| | - F Craes
- II. Physikalisches Institut, Universität zu Köln, Germany.
| | - C Busse
- II. Physikalisches Institut, Universität zu Köln, Germany.
| | - V Caciuc
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich, Germany
| | - N Atodiresei
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich, Germany
| | - S Blügel
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich, Germany
| | - T Michely
- II. Physikalisches Institut, Universität zu Köln, Germany.
| |
Collapse
|
42
|
Abstract
By doping magnetic Ce atoms on a single layer graphene, we report a new and efficient means of modifying structural and electronic properties of graphene that opens a temperature-dependent band gap of size up to 0.5 eV.
Collapse
Affiliation(s)
- Jingul Kim
- Department of Physics
- Pohang University of Science and Technology
- Pohang 37673
- Korea
| | - Paengro Lee
- Department of Physics
- Pohang University of Science and Technology
- Pohang 37673
- Korea
| | - Mintae Ryu
- Department of Physics
- Pohang University of Science and Technology
- Pohang 37673
- Korea
| | - Heemin Park
- Department of Physics
- Pohang University of Science and Technology
- Pohang 37673
- Korea
| | - Jinwook Chung
- Department of Physics
- Pohang University of Science and Technology
- Pohang 37673
- Korea
| |
Collapse
|
43
|
Dong A, Fu Q, Wu H, Wei M, Bao X. Factors controlling the CO intercalation of h-BN overlayers on Ru(0001). Phys Chem Chem Phys 2016; 18:24278-84. [DOI: 10.1039/c6cp03660k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Critical factors influencing the CO intercalation of h-BN were investigated including CO partial pressure, h-BN coverage, and oxygen pre-adsorption on Ru.
Collapse
Affiliation(s)
- Aiyi Dong
- State Key Laboratory of Catalysis
- Dalian Institute of Chemical Physics
- iChEM
- the Chinese Academy of Sciences
- Dalian 116023
| | - Qiang Fu
- State Key Laboratory of Catalysis
- Dalian Institute of Chemical Physics
- iChEM
- the Chinese Academy of Sciences
- Dalian 116023
| | - Hao Wu
- State Key Laboratory of Catalysis
- Dalian Institute of Chemical Physics
- iChEM
- the Chinese Academy of Sciences
- Dalian 116023
| | - Mingming Wei
- State Key Laboratory of Catalysis
- Dalian Institute of Chemical Physics
- iChEM
- the Chinese Academy of Sciences
- Dalian 116023
| | - Xinhe Bao
- State Key Laboratory of Catalysis
- Dalian Institute of Chemical Physics
- iChEM
- the Chinese Academy of Sciences
- Dalian 116023
| |
Collapse
|
44
|
Zhang X, Bian Y, Sun W, Hu T, Liu Y. Electronic and magnetic properties regulation of finite to infinite half sandwich organo-transition-metal-complexes functionalized graphene. RSC Adv 2016. [DOI: 10.1039/c6ra19951h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Total band gaps (Δt) and band gaps of free “graphene”, ignoring impurity bands of TMnOLs (Δg).
Collapse
Affiliation(s)
- Xiuyun Zhang
- School of Physics Science and Technology
- Yangzhou University
- Yangzhou 225002
- China
| | - Yajie Bian
- School of Physics Science and Technology
- Yangzhou University
- Yangzhou 225002
- China
| | - Weikang Sun
- School of Physics Science and Technology
- Yangzhou University
- Yangzhou 225002
- China
| | - Ting Hu
- Department of Applied Physics
- Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education)
- Nanjing University of Science and Technology
- Nanjing
- P. R. China
| | - Yongjun Liu
- School of Physics Science and Technology
- Yangzhou University
- Yangzhou 225002
- China
| |
Collapse
|
45
|
Wei M, Fu Q, Wu H, Dong A, Bao X. Hydrogen Intercalation of Graphene and Boron Nitride Monolayers Grown on Pt(111). Top Catal 2015. [DOI: 10.1007/s11244-015-0516-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
46
|
Verbitskiy NI, Fedorov AV, Profeta G, Stroppa A, Petaccia L, Senkovskiy B, Nefedov A, Wöll C, Usachov DY, Vyalikh DV, Yashina LV, Eliseev AA, Pichler T, Grüneis A. Atomically precise semiconductor--graphene and hBN interfaces by Ge intercalation. Sci Rep 2015; 5:17700. [PMID: 26639608 PMCID: PMC4671056 DOI: 10.1038/srep17700] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/04/2015] [Indexed: 12/04/2022] Open
Abstract
The full exploration of the potential, which graphene offers to nanoelectronics requires its integration into semiconductor technology. So far the real-world applications are limited by the ability to concomitantly achieve large single-crystalline domains on dielectrics and semiconductors and to tailor the interfaces between them. Here we show a new direct bottom-up method for the fabrication of high-quality atomically precise interfaces between 2D materials, like graphene and hexagonal boron nitride (hBN), and classical semiconductor via Ge intercalation. Using angle-resolved photoemission spectroscopy and complementary DFT modelling we observed for the first time that epitaxially grown graphene with the Ge monolayer underneath demonstrates Dirac Fermions unaffected by the substrate as well as an unperturbed electronic band structure of hBN. This approach provides the intrinsic relativistic 2D electron gas towards integration in semiconductor technology. Hence, these new interfaces are a promising path for the integration of graphene and hBN into state-of-the-art semiconductor technology.
Collapse
Affiliation(s)
- N I Verbitskiy
- Faculty of Physics, University of Vienna, Strudlhofgasse 4, A-1090 Vienna, Austria
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straβe 77, D-50937 Cologne, Germany
- Department of Materials Science, Moscow State University, Leninskiye Gory 1/3, 119992, Moscow, Russia
| | - A V Fedorov
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straβe 77, D-50937 Cologne, Germany
- IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany
- St. Petersburg State University, 7/9 Universitetskaya nab, St. Petersburg, 199034, Russia
| | - G Profeta
- Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio 10, I-67100 L'Aquila, Italy
- CNR-SPIN, Via Vetoio 10, I-67100 L'Aquila, Italy
| | - A Stroppa
- CNR-SPIN, Via Vetoio 10, I-67100 L'Aquila, Italy
| | - L Petaccia
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, I-34149 Trieste, Italy
| | - B Senkovskiy
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straβe 77, D-50937 Cologne, Germany
- St. Petersburg State University, 7/9 Universitetskaya nab, St. Petersburg, 199034, Russia
- Institute of Solid State Physics, Dresden University of Technology, Helmholtzstraße 10, D-01062 Dresden, Germany
| | - A Nefedov
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - C Wöll
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - D Yu Usachov
- St. Petersburg State University, 7/9 Universitetskaya nab, St. Petersburg, 199034, Russia
| | - D V Vyalikh
- St. Petersburg State University, 7/9 Universitetskaya nab, St. Petersburg, 199034, Russia
- Institute of Solid State Physics, Dresden University of Technology, Helmholtzstraße 10, D-01062 Dresden, Germany
- IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
- Donostia International Physics Center (DIPC), Departamento de Fisica de Materiales and CFM-MPC UPV/EHU, 20080 San Sebastian, Spain
| | - L V Yashina
- JSC "Giredmet" SRC RF, Tolmachevky St. 5-1 B, 119017 Moscow, Russia
- Department of Chemistry, Moscow State University, Leninskiye Gory 1/3, 119992, Moscow, Russia
| | - A A Eliseev
- Department of Materials Science, Moscow State University, Leninskiye Gory 1/3, 119992, Moscow, Russia
| | - T Pichler
- Faculty of Physics, University of Vienna, Strudlhofgasse 4, A-1090 Vienna, Austria
| | - A Grüneis
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straβe 77, D-50937 Cologne, Germany
| |
Collapse
|
47
|
Huttmann F, Martínez-Galera AJ, Caciuc V, Atodiresei N, Schumacher S, Standop S, Hamada I, Wehling TO, Blügel S, Michely T. Tuning the van der Waals Interaction of Graphene with Molecules via Doping. PHYSICAL REVIEW LETTERS 2015; 115:236101. [PMID: 26684126 DOI: 10.1103/physrevlett.115.236101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Indexed: 06/05/2023]
Abstract
We use scanning tunneling microscopy to visualize and thermal desorption spectroscopy to quantitatively measure that the binding of naphthalene molecules to graphene, a case of pure van der Waals interaction, strengthens with n and weakens with p doping of graphene. Density-functional theory calculations that include the van der Waals interaction in a seamless, ab initio way accurately reproduce the observed trend in binding energies. Based on a model calculation, we propose that the van der Waals interaction is modified by changing the spatial extent of graphene's π orbitals via doping.
Collapse
Affiliation(s)
- Felix Huttmann
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937 Köln, Germany
| | | | - Vasile Caciuc
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Nicolae Atodiresei
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Stefan Schumacher
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937 Köln, Germany
| | - Sebastian Standop
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937 Köln, Germany
| | - Ikutaro Hamada
- International Center for Materials Nanoarchitectonics (WPI-MANA) and Global Research Center for Environment and Energy based on Nanomaterials Science (GREEN), National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Tim O Wehling
- Bremen Center for Computational Material Science (BCCMS), Universität Bremen, Am Fallturm 1a, 28359 Bremen, Germany
| | - Stefan Blügel
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Thomas Michely
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, 50937 Köln, Germany
| |
Collapse
|
48
|
Sala A, Zamborlini G, Menteş TO, Locatelli A. Fabrication of 2D Heterojunction in Graphene via Low Energy N2(+) Irradiation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:5927-5931. [PMID: 26439586 DOI: 10.1002/smll.201501473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 08/14/2015] [Indexed: 06/05/2023]
Abstract
Substitutional doping in graphene is locally induced with very low energy nitrogen ions. Irradiated and nonirradiated areas exhibit different charge carrier densities and are separated by a sharp boundary, stable up to 750 °C. The way towards lithographic control of the electronic properties of graphene by ion irradiation is paved, providing a proof of principle for the fabrication of 2D graphene-based heterojunctions.
Collapse
Affiliation(s)
- Alessandro Sala
- Elettra-Sincrotrone Trieste S.C.p.A, S.S.14-km 163.5, Area Science Park Basovizza, 34149, Trieste, Italy
| | - Giovanni Zamborlini
- Department of Physics, University of Trieste, Via Valerio 2, 34127, Trieste, Italy
- Peter Grünberg Institute (PGI-6), Research Center Jülich, 52425, Jülich, Germany
| | - Tevfik Onur Menteş
- Elettra-Sincrotrone Trieste S.C.p.A, S.S.14-km 163.5, Area Science Park Basovizza, 34149, Trieste, Italy
| | - Andrea Locatelli
- Elettra-Sincrotrone Trieste S.C.p.A, S.S.14-km 163.5, Area Science Park Basovizza, 34149, Trieste, Italy
| |
Collapse
|
49
|
Weatherup RS, D’Arsié L, Cabrero-Vilatela A, Caneva S, Blume R, Robertson J, Schloegl R, Hofmann S. Long-Term Passivation of Strongly Interacting Metals with Single-Layer Graphene. J Am Chem Soc 2015; 137:14358-66. [PMID: 26499041 PMCID: PMC4682849 DOI: 10.1021/jacs.5b08729] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Indexed: 12/21/2022]
Abstract
The long-term (>18 months) protection of Ni surfaces against oxidation under atmospheric conditions is demonstrated by coverage with single-layer graphene, formed by chemical vapor deposition. In situ, depth-resolved X-ray photoelectron spectroscopy of various graphene-coated transition metals reveals that a strong graphene-metal interaction is of key importance in achieving this long-term protection. This strong interaction prevents the rapid intercalation of oxidizing species at the graphene-metal interface and thus suppresses oxidation of the substrate surface. Furthermore, the ability of the substrate to locally form a passivating oxide close to defects or damaged regions in the graphene overlayer is critical in plugging these defects and preventing oxidation from proceeding through the bulk of the substrate. We thus provide a clear rationale for understanding the extent to which two-dimensional materials can protect different substrates and highlight the key implications for applications of these materials as barrier layers to prevent oxidation.
Collapse
Affiliation(s)
- Robert S. Weatherup
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
- Materials Sciences Division, Lawrence Berkeley
National Laboratory, Berkeley, California 94720, United States
| | - Lorenzo D’Arsié
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | | | - Sabina Caneva
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | - Raoul Blume
- Helmholtz-Zentrum Berlin für Materialien
und Energie, D-12489 Berlin, Germany
| | - John Robertson
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | | | - Stephan Hofmann
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| |
Collapse
|
50
|
Kiraly B, Jacobberger RM, Mannix AJ, Campbell GP, Bedzyk MJ, Arnold MS, Hersam MC, Guisinger NP. Electronic and Mechanical Properties of Graphene-Germanium Interfaces Grown by Chemical Vapor Deposition. NANO LETTERS 2015; 15:7414-7420. [PMID: 26506006 DOI: 10.1021/acs.nanolett.5b02833] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Epitaxially oriented wafer-scale graphene grown directly on semiconducting Ge substrates is of high interest for both fundamental science and electronic device applications. To date, however, this material system remains relatively unexplored structurally and electronically, particularly at the atomic scale. To further understand the nature of the interface between graphene and Ge, we utilize ultrahigh vacuum scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) along with Raman and X-ray photoelectron spectroscopy to probe interfacial atomic structure and chemistry. STS reveals significant differences in electronic interactions between graphene and Ge(110)/Ge(111), which is consistent with a model of stronger interaction on Ge(110) leading to epitaxial growth. Raman spectra indicate that the graphene is considerably strained after growth, with more point-to-point variation on Ge(111). Furthermore, this native strain influences the atomic structure of the interface by inducing metastable and previously unobserved Ge surface reconstructions following annealing. These nonequilibrium reconstructions cover >90% of the surface and, in turn, modify both the electronic and mechanical properties of the graphene overlayer. Finally, graphene on Ge(001) represents the extreme strain case, where graphene drives the reorganization of the Ge surface into [107] facets. From this work, it is clear that the interaction between graphene and the underlying Ge is not only dependent on the substrate crystallographic orientation, but is also tunable and strongly related to the atomic reconfiguration of the graphene-Ge interface.
Collapse
Affiliation(s)
- Brian Kiraly
- Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Robert M Jacobberger
- Department of Materials Science and Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Andrew J Mannix
- Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Gavin P Campbell
- Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States
| | - Michael J Bedzyk
- Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States
- Department of Physics and Astronomy, Northwestern University , Evanston, Illinois 60208, United States
| | - Michael S Arnold
- Department of Materials Science and Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Mark C Hersam
- Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Nathan P Guisinger
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
| |
Collapse
|