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Elibol K, Susi T, Mangler C, Eder D, Meyer JC, Kotakoski J, Hobbs RG, van Aken PA, Bayer BC. Linear indium atom chains at graphene edges. NPJ 2D MATERIALS AND APPLICATIONS 2023; 7:2. [PMID: 38665487 PMCID: PMC11041670 DOI: 10.1038/s41699-023-00364-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 01/06/2023] [Indexed: 04/28/2024]
Abstract
The presence of metal atoms at the edges of graphene nanoribbons (GNRs) opens new possibilities toward tailoring their physical properties. We present here formation and high-resolution characterization of indium (In) chains on the edges of graphene-supported GNRs. The GNRs are formed when adsorbed hydrocarbon contamination crystallizes via laser heating into small ribbon-like patches of a second graphitic layer on a continuous graphene monolayer and onto which In is subsequently physical vapor deposited. Using aberration-corrected scanning transmission electron microscopy (STEM), we find that this leads to the preferential decoration of the edges of the overlying GNRs with multiple In atoms along their graphitic edges. Electron-beam irradiation during STEM induces migration of In atoms along the edges of the GNRs and triggers the formation of longer In atom chains during imaging. Density functional theory (DFT) calculations of GNRs similar to our experimentally observed structures indicate that both bare zigzag (ZZ) GNRs as well as In-terminated ZZ-GNRs have metallic character, whereas in contrast, In termination induces metallicity for otherwise semiconducting armchair (AC) GNRs. Our findings provide insights into the creation and properties of long linear metal atom chains at graphitic edges.
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Affiliation(s)
- Kenan Elibol
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, A-1090 Vienna, Austria
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - Toma Susi
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Clemens Mangler
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Dominik Eder
- Institute of Materials Chemistry, Technische Universität Wien (TU Wien), Getreidemarkt 9/165, A-1060 Vienna, Austria
| | - Jannik C. Meyer
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, A-1090 Vienna, Austria
- Institute for Applied Physics, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Jani Kotakoski
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Richard G. Hobbs
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and the SFI Advanced Materials and Bio-Engineering Research Centre (AMBER), Dublin 2, Ireland
- School of Chemistry, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland
| | - Peter A. van Aken
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - Bernhard C. Bayer
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, A-1090 Vienna, Austria
- Institute of Materials Chemistry, Technische Universität Wien (TU Wien), Getreidemarkt 9/165, A-1060 Vienna, Austria
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2
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Ma Z, Lv P, Wu D, Li X, Chu K, Ma D, Jia Y. V (Nb) Single Atoms Anchored by the Edge of a Graphene Armchair Nanoribbon for Efficient Electrocatalytic Nitrogen Reduction: A Theoretical Study. Inorg Chem 2022; 61:17864-17872. [DOI: 10.1021/acs.inorgchem.2c03204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ziyu Ma
- Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng475004, China
- Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Peng Lv
- Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng475004, China
- Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Donghai Wu
- Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng475004, China
- Henan Key Laboratory of Nanocomposites and Applications, Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou450006, China
- Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Xue Li
- Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng475004, China
- Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Ke Chu
- School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou730070, China
| | - Dongwei Ma
- Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng475004, China
- Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Yu Jia
- Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng475004, China
- Joint Center for Theoretical Physics, and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
- International Laboratory for Quantum Functional Materials of Henan, and School of Physics, Zhengzhou University, Zhengzhou450001, China
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3
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Single-Atom-Based Catalysts for Photocatalytic Water Splitting on TiO2 Nanostructures. Catalysts 2022. [DOI: 10.3390/catal12080905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
H2 generation from photocatalytic water splitting is one of the most promising approaches to producing cost-effective and sustainable fuel. Nanostructured TiO2 is a highly stable and efficient semiconductor photocatalyst for this purpose. The main drawback of TiO2 as a photocatalyst is the sluggish charge transfer on the surface of TiO2 that can be tackled to a great extent by the use of platinum group materials (PGM) as co-catalysts. However, the scarcity and high cost of the PGMs is one of the issues that prevent the widespread use of TiO2/PGM systems for photocatalytic H2 generation. Single-atom catalysts which are currently the frontline in the catalysis field can be a favorable path to overcome the scarcity and further advance the use of noble metals. More importantly, single-atom (SA) catalysts simultaneously have the advantage of homogenous and heterogeneous catalysts. This mini-review specifically focuses on the single atom decoration of TiO2 nanostructures for photocatalytic water splitting. The latest progress in fabrication, characterization, and application of single-atoms in photocatalytic H2 generation on TiO2 is reviewed.
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Bhatt MD, Kim H, Kim G. Various defects in graphene: a review. RSC Adv 2022; 12:21520-21547. [PMID: 35975063 PMCID: PMC9347212 DOI: 10.1039/d2ra01436j] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 07/19/2022] [Indexed: 11/23/2022] Open
Abstract
Pristine graphene has been considered one of the most promising materials because of its excellent physical and chemical properties. However, various defects in graphene produced during synthesis or fabrication hinder its performance for applications such as electronic devices, transparent electrodes, and spintronic devices. Due to its intrinsic bandgap and nonmagnetic nature, it cannot be used in nanoelectronics or spintronics. Intrinsic and extrinsic defects are ultimately introduced to tailor electronic and magnetic properties and take advantage of their hidden potential. This article emphasizes the current advancement of intrinsic and extrinsic defects in graphene for potential applications. We also discuss the limitations and outlook for such defects in graphene.
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Affiliation(s)
| | - Heeju Kim
- Hybrid Materials Center, Sejong University Seoul 05006 Korea
- Department of Physics and Astronomy, Sejong University Seoul 05006 Korea
| | - Gunn Kim
- Hybrid Materials Center, Sejong University Seoul 05006 Korea
- Department of Physics and Astronomy, Sejong University Seoul 05006 Korea
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Ngome Okello OF, Doh KY, Kang HS, Song K, Kim YT, Kim KH, Lee D, Choi SY. Visualization of Transition Metal Decoration on h-BN Surface. NANO LETTERS 2021; 21:10562-10569. [PMID: 34618461 DOI: 10.1021/acs.nanolett.1c02198] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Functional h-BN (hexagonal boron nitride) has been prepared via the incorporation of transition metal (TM) impurities like nanoparticles and single atoms. Herein, scanning transmission electron microscopy (STEM) combined with density functional theory (DFT) was employed to study Ta-, Co-, Ni-, and Ir-decorated h-BN monolayers to provide an overview of their preferential site occupancies and morphological evolutions on h-BN. Ta, Ni, Ir, and Co single atoms are all positioned on the nitrogen of h-BN; however DFT predicts the occupancy site can vary with their spin state. In terms of microstructural evolution, Co, Ni, and Ir atoms form 3D nanoclusters while Ta atoms are well dispersed and thus the single Ta atom can be decorated on h-BN. This study highlights on TM/h-BN interaction dynamics and presents an avenue for designing nanostructures for electrocatalytic application.
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Affiliation(s)
- Odongo Francis Ngome Okello
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Kyung-Yeon Doh
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Hye Su Kang
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Kyung Song
- Department of Materials Modelling and Characterization, Korea Institute of Materials Science (KIMS), Changwon 51508, South Korea
| | - Yong-Tae Kim
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Kwang Ho Kim
- Department of Materials Science and Engineering, Pusan National University, Busan 46241, South Korea
| | - Donghwa Lee
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Si-Young Choi
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea
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Gong L, Zhang C, Nie A, Lin C, Zhang H, Gao C, Wang M, Zhang X, Han N, Su H, Lin C, Jin Y, Zhang C, Zhang X, Dai JF, Cheng Y, Huang W. Epitaxial growth of large-grain-size ferromagnetic monolayer CrI 3 for valley Zeeman splitting enhancement. NANOSCALE 2021; 13:2955-2962. [PMID: 33506851 DOI: 10.1039/d0nr08248a] [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
Two-dimensional (2D) magnetic CrI3 has received considerable research attention because of its intrinsic features, including insulation, Ising ferromagnetism, and stacking-order-dependent magnetism, as well as potential in spintronic applications. However, the current strategy for the production of ambient-unstable CrI3 thin layer is limited to mechanical exfoliation, which normally suffers from uncontrollable layer thickness, small size, and low yet unpredictable yield. Here, via a confined vapor epitaxy (CVE) method, we demonstrate the mass production of flower-like CrI3 monolayers on mica. Interestingly, we discovered the crucial role of K ions on the mica surface in determining the morphology of monolayer CrI3, reacting with precursors to form a KIx buffer layer. Meanwhile, the transport agent affects the thickness and size of the as-grown CrI3. Moreover, the Curie temperature of CrI3 is greatly affected by the interaction between CrI3 and the substrate. The monolayer CrI3 on mica could act as a magnetic substrate for valley Zeeman splitting enhancement of WSe2. We reckon our work represents a major advancement in the mass production of monolayer 2D CrI3 and anticipate that our growth strategy may be extended to other transition metal halides.
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Affiliation(s)
- Lipeng Gong
- Key Laboratory of Flexible Electronics & Institute of Advanced Materials, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
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8
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Li R, Shang Y, Xing H, Wang X, Sun M, Qiu W. Orientation Identification of the Black Phosphorus with Different Thickness Based on B 2g Mode Using a Micro-Raman Spectroscope under a Nonanalyzer Configuration. MATERIALS 2020; 13:ma13235572. [PMID: 33297383 PMCID: PMC7768352 DOI: 10.3390/ma13235572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/26/2020] [Accepted: 12/01/2020] [Indexed: 11/25/2022]
Abstract
As an anisotropic material, the unique optoelectronic properties of black phosphorus are obviously anisotropic. Therefore, non-destructive and fast identification of its crystalline orientation is an important condition for its application in optoelectronics research field. Identifying the crystalline orientation of black phosphorus through Ag1 and Ag2 modes under the parallel polarization has high requirements on the Raman system, while in the nonanalyzer configuration, the crystalline orientation of the thick black phosphorus may not be identified through Ag1 and Ag2 modes. This work proposes a new method to identify the crystalline orientation of black phosphorus of different thicknesses. This method is conducted under the nonanalyzer configuration by B2g mode. The results show that B2g mode has a good consistency in the identification of crystalline orientations. In this paper, a theoretical model is established to study the angle-resolved Raman results of B2g mode. The new method can accurately identify the crystalline orientation with different layers of black phosphorus without misidentification.
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Affiliation(s)
| | | | | | | | | | - Wei Qiu
- Correspondence: ; Tel.: +86-1392-046-2608
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9
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Zhuo HY, Zhang X, Liang JX, Yu Q, Xiao H, Li J. Theoretical Understandings of Graphene-based Metal Single-Atom Catalysts: Stability and Catalytic Performance. Chem Rev 2020; 120:12315-12341. [PMID: 33112608 DOI: 10.1021/acs.chemrev.0c00818] [Citation(s) in RCA: 152] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Research on heterogeneous single-atom catalysts (SACs) has become an emerging frontier in catalysis science because of their advantages in high utilization of noble metals, precisely identified active sites, high selectivity, and tunable activity. Graphene, as a one-atom-thick two-dimensional carbon material with unique structural and electronic properties, has been reported to be a superb support for SACs. Herein, we provide an overview of recent progress in investigations of graphene-based SACs. Among the large number of publications, we will selectively focus on the stability of metal single-atoms (SAs) anchored on different sites of graphene support and the catalytic performances of graphene-based SACs for different chemical reactions, including thermocatalysis and electrocatalysis. We will summarize the fundamental understandings on the electronic structures and their intrinsic connection with catalytic properties of graphene-based SACs, and also provide a brief perspective on the future design of efficient SACs with graphene and graphene-like materials.
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Affiliation(s)
- Hong-Ying Zhuo
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.,State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum, Beijing 102249, China
| | - Xin Zhang
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum, Beijing 102249, China
| | - Jin-Xia Liang
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Qi Yu
- School of Materials Science and Engineering, Institute of Graphene at Shaanxi Key Laboratory of Catalysis, Shaanxi University of Technology, Hanzhong 723001, China
| | - Hai Xiao
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.,Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
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10
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Lang R, Du X, Huang Y, Jiang X, Zhang Q, Guo Y, Liu K, Qiao B, Wang A, Zhang T. Single-Atom Catalysts Based on the Metal–Oxide Interaction. Chem Rev 2020; 120:11986-12043. [DOI: 10.1021/acs.chemrev.0c00797] [Citation(s) in RCA: 203] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Rui Lang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Xiaorui Du
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Yike Huang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xunzhu Jiang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qian Zhang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yalin Guo
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaipeng Liu
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Botao Qiao
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Aiqin Wang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Tao Zhang
- CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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11
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Kaiser SK, Chen Z, Faust Akl D, Mitchell S, Pérez-Ramírez J. Single-Atom Catalysts across the Periodic Table. Chem Rev 2020; 120:11703-11809. [PMID: 33085890 DOI: 10.1021/acs.chemrev.0c00576] [Citation(s) in RCA: 347] [Impact Index Per Article: 86.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Isolated atoms featuring unique reactivity are at the heart of enzymatic and homogeneous catalysts. In contrast, although the concept has long existed, single-atom heterogeneous catalysts (SACs) have only recently gained prominence. Host materials have similar functions to ligands in homogeneous catalysts, determining the stability, local environment, and electronic properties of isolated atoms and thus providing a platform for tailoring heterogeneous catalysts for targeted applications. Within just a decade, we have witnessed many examples of SACs both disrupting diverse fields of heterogeneous catalysis with their distinctive reactivity and substantially enriching our understanding of molecular processes on surfaces. To date, the term SAC mostly refers to late transition metal-based systems, but numerous examples exist in which isolated atoms of other elements play key catalytic roles. This review provides a compositional encyclopedia of SACs, celebrating the 10th anniversary of the introduction of this term. By defining single-atom catalysis in the broadest sense, we explore the full elemental diversity, joining different areas across the whole periodic table, and discussing historical milestones and recent developments. In particular, we examine the coordination structures and associated properties accessed through distinct single-atom-host combinations and relate them to their main applications in thermo-, electro-, and photocatalysis, revealing trends in element-specific evolution, host design, and uses. Finally, we highlight frontiers in the field, including multimetallic SACs, atom proximity control, and possible applications for multistep and cascade reactions, identifying challenges, and propose directions for future development in this flourishing field.
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Affiliation(s)
- Selina K Kaiser
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich, Switzerland
| | - Zupeng Chen
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich, Switzerland
| | - Dario Faust Akl
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich, Switzerland
| | - Sharon Mitchell
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich, Switzerland
| | - Javier Pérez-Ramírez
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich, Switzerland
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Gerber IC, Serp P. A Theory/Experience Description of Support Effects in Carbon-Supported Catalysts. Chem Rev 2019; 120:1250-1349. [DOI: 10.1021/acs.chemrev.9b00209] [Citation(s) in RCA: 274] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Iann C. Gerber
- LPCNO, Université de Toulouse, CNRS, INSA, UPS, 135 avenue de Rangueil, F-31077 Toulouse, France
| | - Philippe Serp
- LCC-CNRS, Université de Toulouse, UPR 8241 CNRS, INPT, 31400 Toulouse, France
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14
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Hernández-Vázquez EE, Munoz F, López-Moreno S, Morán-López JL. First-principles study of Ni adatom migration on graphene with vacancies. RSC Adv 2019; 9:18823-18834. [PMID: 35516868 PMCID: PMC9065389 DOI: 10.1039/c9ra00999j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/01/2019] [Indexed: 12/02/2022] Open
Abstract
A theoretical study based on first-principles calculations about the interaction and diffusion of Ni atoms on pristine graphene and graphene with a single vacancy is presented. In the first case, we explored the structural changes due to the adsorption of Ni on graphene and the effects on the electronic structure. In the case of graphene with a vacancy, we analyzed the impact of the adsorbed Ni atom on the distortion of the graphene structure and how it depends on the distance from the graphene defect. In the analysis, we observed the changes in the electron localization function and the charge density. By knowing the interaction map of Ni with graphene, and the structural changes of the network, we performed energy barrier calculations within the climbing image nudged elastic band methodology to study the nickel diffusion. Finally, we explored how the vacancy and structural distortions affect the minimum energy paths and the saddle points for nickel moving away, around, and towards the vacancy.
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Affiliation(s)
- E E Hernández-Vázquez
- División de Materiales Avanzados, IPICYT Camino a la Presa San José 2055 San Luis Potosí S.L.P. 78216 Mexico
| | - F Munoz
- Departamento de Física, Facultad de Ciencias, Universidad de Chile Santiago Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA) Santiago Chile
| | - S López-Moreno
- CONACYT - División de Materiales Avanzados, IPICYT Camino a la Presa San José 2055 San Luis Potosí S.L.P. 78216 Mexico
| | - J L Morán-López
- División de Materiales Avanzados, IPICYT Camino a la Presa San José 2055 San Luis Potosí S.L.P. 78216 Mexico
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15
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Single Au Atoms on the Surface of N-Free and N-Doped Carbon: Interaction with Formic Acid and Methanol Molecules. Top Catal 2019. [DOI: 10.1007/s11244-019-01166-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Wella SA, Hamamoto Y, Morikawa Y, Hamada I. Platinum single-atom adsorption on graphene: a density functional theory study. NANOSCALE ADVANCES 2019; 1:1165-1174. [PMID: 36133205 PMCID: PMC9417699 DOI: 10.1039/c8na00236c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 12/08/2018] [Indexed: 06/16/2023]
Abstract
Single-atom catalysis, which utilizes single atoms as active sites, is one of the most promising ways to enhance the catalytic activity and to reduce the amount of precious metals used. Platinum atoms deposited on graphene are reported to show enhanced catalytic activity for some chemical reactions, e.g. methanol oxidation in direct methanol fuel cells. However, the precise atomic structure, the key to understand the origin of the improved catalytic activity, is yet to be clarified. Here, we present a computational study to investigate the structure of platinum adsorbed on graphene with special emphasis on the edges of graphene nanoribbons. By means of density functional theory based thermodynamics, we find that single platinum atoms preferentially adsorb on the substitutional carbon sites at the hydrogen terminated graphene edge. The structures are further corroborated by the core level shift calculations. Large positive core level shifts indicate the strong interaction between single Pt atoms and graphene. The atomistic insight obtained in this study will be a basis for further investigation of the activity of single-atom catalysts based on platinum and graphene related materials.
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Affiliation(s)
- Sasfan Arman Wella
- Department of Precision Science and Technology, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
- Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jalan Ganesha 10 Bandung 40132 Indonesia
| | - Yuji Hamamoto
- Department of Precision Science and Technology, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
- Element Strategy Initiative for Catalyst and Batteries, Kyoto University Katsura Kyoto 615-8520 Japan
| | - Yoshitada Morikawa
- Department of Precision Science and Technology, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
- Element Strategy Initiative for Catalyst and Batteries, Kyoto University Katsura Kyoto 615-8520 Japan
- Research Center for Ultra-Precision Science and Technology, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
| | - Ikutaro Hamada
- Department of Precision Science and Technology, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan
- Element Strategy Initiative for Catalyst and Batteries, Kyoto University Katsura Kyoto 615-8520 Japan
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Axet MR, Durand J, Gouygou M, Serp P. Surface coordination chemistry on graphene and two-dimensional carbon materials for well-defined single atom supported catalysts. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2019. [DOI: 10.1016/bs.adomc.2019.01.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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18
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Affiliation(s)
| | - Philippe Serp
- LCC CNRS-UPR 8241 ENSIACET Université de Toulouse Toulouse France
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Peng Y, Lu B, Chen S. Carbon-Supported Single Atom Catalysts for Electrochemical Energy Conversion and Storage. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1801995. [PMID: 30132997 DOI: 10.1002/adma.201801995] [Citation(s) in RCA: 235] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/30/2018] [Indexed: 05/27/2023]
Abstract
Single atoms of select transition metals supported on carbon substrates have emerged as a unique system for electrocatalysis because of maximal atom utilization (≈100%) and high efficiency for a range of reactions involved in electrochemical energy conversion and storage, such as the oxygen reduction, oxygen evolution, hydrogen evolution, and CO2 reduction reactions. Herein, the leading strategies for the preparation of single atom catalysts are summarized, and the electrocatalytic performance of the resulting samples for the various reactions is discussed. In general, the carbon substrate not only provides a stabilizing matrix for the metal atoms, but also impacts the electronic density of the metal atoms due to strong interfacial interactions, which may lead to the formation of additional active sites by the adjacent carbon atoms and hence enhanced electrocatalytic activity. This necessitates a detailed understanding of the material structures at the atomic level, a critical step in the construction of a relevant structural model for theoretical simulations and calculations. Finally, a perspective is included highlighting the promises and challenges for the future development of carbon-supported single atom catalysts in electrocatalysis.
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Affiliation(s)
- Yi Peng
- Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Bingzhang Lu
- Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Shaowei Chen
- Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, CA, 95064, USA
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20
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Gao G, Bottle S, Du A. Understanding the activity and selectivity of single atom catalysts for hydrogen and oxygen evolution via ab initial study. Catal Sci Technol 2018. [DOI: 10.1039/c7cy02463k] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To identify the specific activity sites for both the HER and OER in experimental realized single transition-metal atom decorated graphene sheets, we assume the number of metal–C bonds (coordination) determines the adsorption strength of reaction intermediates on the metal atom sites.
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Affiliation(s)
- Guoping Gao
- School of Chemistry
- Physics and Mechanical Engineering
- Queensland University of Technology
- Brisbane
- Australia
| | - Steven Bottle
- School of Chemistry
- Physics and Mechanical Engineering
- Queensland University of Technology
- Brisbane
- Australia
| | - Aijun Du
- School of Chemistry
- Physics and Mechanical Engineering
- Queensland University of Technology
- Brisbane
- Australia
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21
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Chen Q, Robertson AW, He K, Gong C, Yoon E, Kirkland AI, Lee GD, Warner JH. Elongated Silicon-Carbon Bonds at Graphene Edges. ACS NANO 2016; 10:142-149. [PMID: 26619146 DOI: 10.1021/acsnano.5b06050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We study the bond lengths of silicon (Si) atoms attached to both armchair and zigzag edges using aberration corrected transmission electron microscopy with monochromation of the electron beam. An in situ heating holder is used to perform imaging of samples at 800 °C in order to reduce chemical etching effects that cause rapid structure changes of graphene edges at room temperature under the electron beam. We provide detailed bond length measurements for Si atoms both attached to edges and also as near edge substitutional dopants. Edge reconstruction is also involved with the addition of Si dopants. Si atoms bonded to the edge of graphene are compared to substitutional dopants in the bulk lattice and reveal reduced out-of-plane distortion and bond elongation. An extended linear array of Si atoms at the edge is found to be energy-favorable due to inter-Si interactions. These results provide detailed structural information about the Si-C bonds in graphene, which may have importance in future catalytic and electronic applications.
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Affiliation(s)
- Qu Chen
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Alex W Robertson
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Kuang He
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Chuncheng Gong
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Euijoon Yoon
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Angus I Kirkland
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Gun-Do Lee
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Jamie H Warner
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
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22
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23
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Koskinen P, Korhonen T. Plenty of motion at the bottom: atomically thin liquid gold membrane. NANOSCALE 2015; 7:10140-10145. [PMID: 25986207 DOI: 10.1039/c5nr01849h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The discovery of graphene some ten years ago was the first proof of a free-standing two-dimensional (2D) solid phase. Here, using quantum molecular dynamics simulations of nanoscale gold patches suspended in graphene pores, we predict the existence of an atomically thin, free-standing 2D liquid phase. The liquid phase, enabled by the exceptional planar stability of gold due to relativistic effects, demonstrates extreme fluxionality of metal nanostructures and opens possibilities for a variety of nanoscale phenomena.
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Affiliation(s)
- Pekka Koskinen
- Nanoscience Center, Department of Physics, University of Jyvaskyla, 40014 Jyväskylä, Finland.
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24
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Transmission electron microscopy of thiol-capped Au clusters on C: Structure and electron irradiation effects. Micron 2015; 70:41-9. [PMID: 25554918 DOI: 10.1016/j.micron.2014.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 12/03/2014] [Accepted: 12/03/2014] [Indexed: 11/24/2022]
Abstract
High-resolution transmission electron microscopy is used to study interactions between thiol-capped Au clusters and amorphous C support films. The morphologies of the clusters are found to depend both on their size and on the local structure of the underlying C. When the C is amorphous, larger Au clusters are crystalline, while smaller clusters are typically disordered. When the C is graphitic, the Au particles adopt either elongated shapes that maximize their contact with the edge of the C film or planar arrays when they contain few Au atoms. We demonstrate the influence of electron beam irradiation on the structure, shape and stability of the Au clusters, as well as on the formation of holes bounded by terraces of graphitic lamellae in the underlying C.
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25
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Sirijaraensre J, Limtrakul J. Modification of the catalytic properties of the Au4 nanocluster for the conversion of methane-to-methanol: synergistic effects of metallic adatoms and a defective graphene support. Phys Chem Chem Phys 2015; 17:9706-15. [DOI: 10.1039/c4cp05131a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By means of the density functional theory calculations, enhanced catalytic activity of Au4 cluster for the partial oxidation of methane with the N2O oxidant is observed when the cluster is deposited on top of the Pd/graphene.
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Affiliation(s)
- J. Sirijaraensre
- Department of Chemistry and NANOTEC Center for Nanoscale Materials Design for Green Nanotechnology
- Faculty of Science
- Kasetsart University
- Bangkok 10900
- Thailand
| | - J. Limtrakul
- Department of Chemistry and NANOTEC Center for Nanoscale Materials Design for Green Nanotechnology
- Faculty of Science
- Kasetsart University
- Bangkok 10900
- Thailand
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26
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Wu P, Du P, Zhang H, Cai C. Graphyne-supported single Fe atom catalysts for CO oxidation. Phys Chem Chem Phys 2015; 17:1441-9. [DOI: 10.1039/c4cp04181j] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We demonstrate that graphyne is a good substrate for single Fe atom catalysts, which have high catalytic activity for CO oxidation.
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Affiliation(s)
- Ping Wu
- Jiangsu Key Laboratory of New Power Batteries
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials
- College of Chemistry and Materials Science
- Nanjing Normal University
- Nanjing 210097
| | - Pan Du
- Jiangsu Key Laboratory of New Power Batteries
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials
- College of Chemistry and Materials Science
- Nanjing Normal University
- Nanjing 210097
| | - Hui Zhang
- Jiangsu Key Laboratory of New Power Batteries
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials
- College of Chemistry and Materials Science
- Nanjing Normal University
- Nanjing 210097
| | - Chenxin Cai
- Jiangsu Key Laboratory of New Power Batteries
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials
- College of Chemistry and Materials Science
- Nanjing Normal University
- Nanjing 210097
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27
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Direct in situ observations of single Fe atom catalytic processes and anomalous diffusion at graphene edges. Proc Natl Acad Sci U S A 2014; 111:15641-6. [PMID: 25331874 DOI: 10.1073/pnas.1412962111] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Single-atom catalysts are of great interest because of their high efficiency. In the case of chemically deposited sp(2) carbon, the implementation of a single transition metal atom for growth can provide crucial insight into the formation mechanisms of graphene and carbon nanotubes. This knowledge is particularly important if we are to overcome fabrication difficulties in these materials and fully take advantage of their distinct band structures and physical properties. In this work, we present atomically resolved transmission EM in situ investigations of single Fe atoms at graphene edges. Our in situ observations show individual iron atoms diffusing along an edge either removing or adding carbon atoms (viz., catalytic action). The experimental observations of the catalytic behavior of a single Fe atom are in excellent agreement with supporting theoretical studies. In addition, the kinetics of Fe atoms at graphene edges are shown to exhibit anomalous diffusion, which again, is in agreement with our theoretical investigations.
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28
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Barry NPE, Pitto-Barry A, Sanchez AM, Dove AP, Procter RJ, Soldevila-Barreda JJ, Kirby N, Hands-Portman I, Smith CJ, O'Reilly RK, Beanland R, Sadler PJ. Fabrication of crystals from single metal atoms. Nat Commun 2014; 5:3851. [PMID: 24861089 PMCID: PMC4050283 DOI: 10.1038/ncomms4851] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Accepted: 04/10/2014] [Indexed: 11/16/2022] Open
Abstract
Metal nanocrystals offer new concepts for the design of nanodevices with a range of potential applications. Currently the formation of metal nanocrystals cannot be controlled at the level of individual atoms. Here we describe a new general method for the fabrication of multi-heteroatom-doped graphitic matrices decorated with very small, ångström-sized, three-dimensional (3D)-metal crystals of defined size. We irradiate boron-rich precious-metal-encapsulated self-spreading polymer micelles with electrons and produce, in real time, a doped graphitic support on which individual osmium atoms hop and migrate to form 3D-nanocrystals, as small as 15 Å in diameter, within 1 h. Crystal growth can be observed, quantified and controlled in real time. We also synthesize the first examples of mixed ruthenium–osmium 3D-nanocrystals. This technology not only allows the production of ångström-sized homo- and hetero-crystals, but also provides new experimental insight into the dynamics of nanocrystals and pathways for their assembly from single atoms. Metal nanocrystals are used in an ever growing list of applications, but precise control and understanding of their formation can be difficult. Here, the authors show a route that allows the controlled formation of metal nanocrystals to be carried out and observed at an atom-by-atom level.
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Affiliation(s)
- Nicolas P E Barry
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Anaïs Pitto-Barry
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Ana M Sanchez
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Andrew P Dove
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Richard J Procter
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | | | - Nigel Kirby
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Ian Hands-Portman
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Corinne J Smith
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Rachel K O'Reilly
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Richard Beanland
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Peter J Sadler
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
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29
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Xiao BB, Lang XY, Jiang Q. Pt monatomic wire supported on graphene nanoribbon for oxygen reduction reaction. RSC Adv 2014. [DOI: 10.1039/c4ra03387f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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30
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Plant SR, Cao L, Yin F, Wang ZW, Palmer RE. Size-dependent propagation of Au nanoclusters through few-layer graphene. NANOSCALE 2014; 6:1258-63. [PMID: 24242001 DOI: 10.1039/c3nr04770a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report the size-dependent propagation of gold nanoclusters through few-layer graphene (FLG). We employ aberration-corrected scanning transmission electron microscopy (STEM) to track the fate of Au55 and Au923 clusters that have been deposited, independently and isoenergetically, onto suspended FLG films using cluster beam deposition. We demonstrate that Au55 clusters penetrate through the FLG, whereas the monodisperse Au923 clusters reside at the surface. Our approach offers a route to the controlled incorporation of dopant nanoparticles and the generation of nanoscale defects in graphene.
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Affiliation(s)
- Simon R Plant
- Nanoscale Physics Research Laboratory, School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UK.
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31
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Graphene–Environmental and Sensor Applications. NANOTECHNOLOGY FOR WATER TREATMENT AND PURIFICATION 2014. [DOI: 10.1007/978-3-319-06578-6_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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32
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Gong C, Robertson AW, He K, Ford C, Watt AAR, Warner JH. Interactions of Pb and Te atoms with graphene. Dalton Trans 2014; 43:7442-8. [DOI: 10.1039/c4dt00143e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Skowron ST, Lebedeva IV, Popov AM, Bichoutskaia E. Approaches to modelling irradiation-induced processes in transmission electron microscopy. NANOSCALE 2013; 5:6677-6692. [PMID: 23783785 DOI: 10.1039/c3nr02130k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The recent progress in high-resolution transmission electron microscopy (HRTEM) has given rise to the possibility of in situ observations of nanostructure transformations and chemical reactions induced by electron irradiation. In this article we briefly summarise experimental observations and discuss in detail atomistic modelling of irradiation-induced processes in HRTEM, as well as mechanisms of such processes recognised due to modelling. Accurate molecular dynamics (MD) techniques based on first principles or tight-binding models are employed in the analysis of single irradiation-induced events, and classical MD simulations are combined with a kinetic Monte Carlo algorithm to simulate continuous irradiation of nanomaterials. It has been shown that sulphur-terminated graphene nanoribbons are formed inside carbon nanotubes as a result of an irradiation-selective chemical reaction. The process of fullerene formation in HRTEM during continuous electron irradiation of a small graphene flake has been simulated, and mechanisms driving this transformation analysed.
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Affiliation(s)
- Stephen T Skowron
- Department of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK
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34
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Tang Q, Zhou Z, Chen Z. Graphene-related nanomaterials: tuning properties by functionalization. NANOSCALE 2013; 5:4541-83. [PMID: 23443470 DOI: 10.1039/c3nr33218g] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this review, we discuss the most recent progress on graphene-related nanomaterials, including doped graphene and derived graphene nanoribbons, graphene oxide, graphane, fluorographene, graphyne, graphdiyne, and porous graphene, from both experimental and theoretical perspectives, and emphasize tuning their stability, electronic and magnetic properties by chemical functionalization.
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Affiliation(s)
- Qing Tang
- Tianjin Key Laboratory of Metal and Molecule Based Material Chemistry, Institute of New Energy Material Chemistry, Computational Centre for Molecule Science, Nankai University, Tianjin 300071, PR China
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35
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Robertson AW, Warner JH. Atomic resolution imaging of graphene by transmission electron microscopy. NANOSCALE 2013; 5:4079-93. [PMID: 23595204 DOI: 10.1039/c3nr00934c] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The atomic structure of a material influences its electronic, chemical, magnetic and mechanical properties. Characterising carbon nanomaterials, such as fullerenes, nanotubes and graphene, at the atomic level is challenging due to their chemical reactivity and low atomic mass. Transmission electron microscopy and scanning probe microscopy are two of the leading methods for imaging graphene at the atomic level. Here, we report on recent advances in atomic resolution imaging of graphene using aberration-corrected high resolution transmission electron microscopy and how it has revealed many of the structural deviations from the pristine monolayer form. Structures in graphene such as vacancy defects, edges, grain boundaries, linear chains, impurity dopants, layer number, layer stacking and bond rotations are explored.
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36
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Robertson AW, Montanari B, He K, Kim J, Allen CS, Wu YA, Olivier J, Neethling J, Harrison N, Kirkland AI, Warner JH. Dynamics of single Fe atoms in graphene vacancies. NANO LETTERS 2013; 13:1468-1475. [PMID: 23517297 DOI: 10.1021/nl304495v] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Focused electron beam irradiation has been used to create mono and divacancies in graphene within a defined area, which then act as trap sites for mobile Fe atoms initially resident on the graphene surface. Aberration-corrected transmission electron microscopy at 80 kV has been used to study the real time dynamics of Fe atoms filling the vacancy sites in graphene with atomic resolution. We find that the incorporation of a dopant atom results in pronounced displacements of the surrounding carbon atoms of up to 0.5 Å, which is in good agreement with density functional theory calculations. Once incorporated into the graphene lattice, Fe atoms can transition to adjacent lattice positions and reversibly switch their bonding between four and three nearest neighbors. The C atoms adjacent to the Fe atoms are found to be more susceptible to Stone-Wales type bond rotations with these bond rotations associated with changes in the dopant bonding configuration. These results demonstrate the use of controlled electron beam irradiation to incorporate dopants into the graphene lattice with nanoscale spatial control.
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Affiliation(s)
- Alex W Robertson
- Department of Materials, University of Oxford, Oxford, United Kingdom
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37
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Wang H, Li K, Yao Y, Wang Q, Cheng Y, Schwingenschlögl U, Zhang XX, Yang W. Unraveling the atomic structure of ultrafine iron clusters. Sci Rep 2012; 2:995. [PMID: 23251781 PMCID: PMC3524523 DOI: 10.1038/srep00995] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 11/30/2012] [Indexed: 11/30/2022] Open
Abstract
Unraveling the atomic structures of ultrafine iron clusters is critical to understanding their size-dependent catalytic effects and electronic properties. Here, we describe the stable close-packed structure of ultrafine Fe clusters for the first time, thanks to the superior properties of graphene, including the monolayer thickness, chemical inertness, mechanical strength, electrical and thermal conductivity. These clusters prefer to take regular planar shapes with morphology changes by local atomic shuffling, as suggested by the early hypothesis of solid-solid transformation. Our observations differ from observations from earlier experimental study and theoretical model, such as icosahedron, decahedron or cuboctahedron. No interaction was observed between Fe atoms or clusters and pristine graphene. However, preferential carving, as observed by other research groups, can be realized only when Fe clusters are embedded in graphene. The techniques introduced here will be of use in investigations of other clusters or even single atoms or molecules.
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Affiliation(s)
- Hongtao Wang
- Institute of Applied Mechanics, Zhejiang University, Hangzhou 310027, China
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38
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Zhu W, Wang H, Yang W. Evolution of graphene nanoribbons under low-voltage electron irradiation. NANOSCALE 2012; 4:4555-4561. [PMID: 22699261 DOI: 10.1039/c2nr30648d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Though the all-semiconducting nature of ultrathin graphene nanoribbons (GNRs) has been demonstrated in field-effect transistors operated at room temperature with ∼10(5) on-off current ratios, the borderline for the potential of GNRs is still untouched. There remains a great challenge in fabricating even thinner GNRs with precise width, known edge configurations and specified crystallographic orientations. Unparalleled to other methods, low-voltage electron irradiation leads to a continuous reduction in width to a sub-nanometer range until the occurrence of structural instability. The underlying mechanisms have been investigated by the molecular dynamics method herein, combined with in situ aberration-corrected transmission electron microscopy and density functional theory calculations. The structural evolution reveals that the zigzag edges are dynamically more stable than the chiral ones. Preferential bond breaking induces atomic rings and dangling bonds as the initial defects. The defects grow, combine and reconstruct to complex edge structures. Dynamic recovery is enhanced by thermal activation, especially in cooperation with electron irradiation. Roughness develops under irradiation and reaches a plateau less than 1 nm for all edge configurations after longtime exposure. These features render low-voltage electron irradiation an attractive technique in the fabrication of ultrathin GNRs for exploring the ultimate electronic properties.
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Affiliation(s)
- Wenpeng Zhu
- AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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