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Luo Y, He Y, Ding Y, Zuo L, Zhong C, Ma Y, Sun M. Defective Biphenylene as High-Efficiency Hydrogen Evolution Catalysts. Inorg Chem 2024; 63:1136-1141. [PMID: 38160412 DOI: 10.1021/acs.inorgchem.3c03503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Electrocatalysts play a pivotal role in advancing the application of water splitting for hydrogen production. This research unveils the potential of defective biphenylenes as high-efficiency catalysts for the hydrogen evolution reaction. Using first-principles simulations, we systematically investigated the structure, stability, and catalytic performance of defective biphenylenes. Our findings unveil that defect engineering significantly enhances the electrocatalytic activity for hydrogen evolution. Specifically, biphenylene with a double-vacancy defect exhibits an outstanding Gibbs free energy of -0.08 eV, surpassing that of Pt, accompanied by a remarkable exchange current density of -3.08 A cm-2, also surpassing that of Pt. Furthermore, we find the preference for the Volmer-Heyrovsky mechanism in the hydrogen evolution reaction, with a low energy barrier of 0.80 eV. This research provides a promising avenue for developing novel metal-free electrocatalysts for water splitting with earth-abundant carbon elements, making a significant step toward sustainable hydrogen production.
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Affiliation(s)
- Yi Luo
- School of Mechanical Engineering, Jiangsu Ocean University, Lianyungang 222005, China
- Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, Jiangsu Ocean University, Lianyungang 222005, China
| | - Yiqiang He
- School of Mechanical Engineering, Jiangsu Ocean University, Lianyungang 222005, China
| | - Yunfei Ding
- School of Mechanical Engineering, Jiangsu Ocean University, Lianyungang 222005, China
| | - Lijie Zuo
- School of Mechanical Engineering, Jiangsu Ocean University, Lianyungang 222005, China
| | - Chengyong Zhong
- College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China
| | - Yinchang Ma
- Physical Sciences and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Minglei Sun
- Department of Physics and NANOlab Center of Excellence, University of Antwerp, Antwerp 2020, Belgium
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2
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Santos E. Structural Dynamics in the Presence of Water of Graphene Bilayers with Defects. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2038. [PMID: 37513049 PMCID: PMC10385876 DOI: 10.3390/nano13142038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/01/2023] [Accepted: 07/04/2023] [Indexed: 07/30/2023]
Abstract
The dynamics of a bilayer of graphene containing one mono-vacancy in the top layer has been investigated in the framework of DFTB in the absence and in the presence of water. Due to the speed of the code, we can describe details of the behavior, which are not directly accessible experimentally and cannot be treated by DFT or classical molecular dynamics. The presence of water enhances the displacement of carbon atoms in the perpendicular direction to the surface. Our results explain very well a variety of experimental findings. In particular, the stabilization of the Jahn-Teller distortion by hydrogenation of one of the carbon atoms at the edge of a mono-vacancy has been elucidated. This work is the first analysis of the behavior of a graphene vacancy at room temperature in contact with water based on a quantum mechanical molecular dynamics method, where both graphene and solvent are treated at the same level.
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Affiliation(s)
- Elizabeth Santos
- Institute of Theoretical Chemistry, Ulm University, Mez-Starck-Haus, Oberberghof 7, 89081 Ulm, Germany
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3
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F Morgado F, Stephenson L, Rousseau L, Vurpillot F, Evertz S, Schneider JM, Gault B. Improving Spatial and Elemental Associations in Analytical Field Ion Microscopy. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1077-1086. [PMID: 37749678 DOI: 10.1093/micmic/ozad039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 01/20/2023] [Accepted: 03/10/2023] [Indexed: 09/27/2023]
Abstract
Chemically resolved atomic resolution imaging can give fundamental information about material properties. However, even today, a technique capable of such achievement is still only an ambition. Here, we take further steps in developing the analytical field ion microscopy (aFIM), which combines the atomic spatial resolution of field ion microscopy (FIM) with the time-of-flight spectrometry of atom probe tomography (APT). To improve the performance of aFIM that are limited in part by a high level of background, we implement bespoke flight path time-of-flight corrections normalized by the ion flight distances traversed in electrostatic simulations modeled explicitly for an atom probe chamber. We demonstrate effective filtering in the field evaporation events upon spatially and temporally correlated multiples, increasing the mass spectrum's signal-to-background. In an analysis of pure tungsten, mass peaks pertaining to individual W isotopes can be distinguished and identified, with the signal-to-background improving by three orders of magnitude over the raw data. We also use these algorithms for the analysis of a CoTaB amorphous film to demonstrate application of aFIM beyond pure metals and binary alloys. These approaches facilitate elemental identification of the FIM-imaged surface atoms, making analytical FIM more precise and reliable.
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Affiliation(s)
- Felipe F Morgado
- Department of Metal Physics and Alloy Design, Max Planck Institut für Eisenforschung GmbH, Düsseldorf 40237, Germany
| | - Leigh Stephenson
- Department of Metal Physics and Alloy Design, Max Planck Institut für Eisenforschung GmbH, Düsseldorf 40237, Germany
| | - Loic Rousseau
- Groupe de Physique des Matériaux, University and INSA of Rouen, CNRS, Normandie University, Avenue de l'université, Rouen 76000, France
| | - François Vurpillot
- Groupe de Physique des Matériaux, University and INSA of Rouen, CNRS, Normandie University, Avenue de l'université, Rouen 76000, France
| | - Simon Evertz
- Department of Metal Physics and Alloy Design, Max Planck Institut für Eisenforschung GmbH, Düsseldorf 40237, Germany
- Materials Chemistry, RWTH Aachen University, Kopernikusstr 10, Aachen 52074, Germany
| | - Jochen M Schneider
- Materials Chemistry, RWTH Aachen University, Kopernikusstr 10, Aachen 52074, Germany
| | - Baptiste Gault
- Department of Metal Physics and Alloy Design, Max Planck Institut für Eisenforschung GmbH, Düsseldorf 40237, Germany
- Department of Materials, Royal School of Mines, Prince Consort Road, Imperial College London, London, SW7 2AZ, UK
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4
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Xu X, Guo T, Kim H, Hota MK, Alsaadi RS, Lanza M, Zhang X, Alshareef HN. Growth of 2D Materials at the Wafer Scale. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108258. [PMID: 34860446 DOI: 10.1002/adma.202108258] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/29/2021] [Indexed: 06/13/2023]
Abstract
Wafer-scale growth has become a critical bottleneck for scaling up applications of van der Waal (vdW) layered 2D materials in high-end electronics and optoelectronics. Most vdW 2D materials are initially obtained through top-down synthesis methods, such as exfoliation, which can only prepare small flakes on a micrometer scale. Bottom-up growth can enable 2D flake growth over a large area. However, seamless merging of these flakes to form large-area continuous films with well-controlled layer thickness and lattice orientation is still a significant challenge. This review briefly introduces several vdW layered 2D materials covering their lattice structures, representative physical properties, and potential roles in large-scale applications. Then, several methods used to grow vdW layered 2D materials at the wafer scale are reviewed in depth. In particular, three strategies are summarized that enable 2D film growth with a single-crystalline structure over the whole wafer: growth of an isolated domain, growth of unidirectional domains, and conversion of oriented precursors. After that, the progress in using wafer-scale 2D materials in integrated devices and advanced epitaxy is reviewed. Finally, future directions in the growth and scaling of vdW layered 2D materials are discussed.
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Affiliation(s)
- Xiangming Xu
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Tianchao Guo
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Hyunho Kim
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Mrinal K Hota
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Rajeh S Alsaadi
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Mario Lanza
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Xixiang Zhang
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Husam N Alshareef
- Materials Science and Engineering, Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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5
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Allen CS, Ghamouss F, Boujibar O, Harris PJF. Aberration-corrected transmission electron microscopy of a non-graphitizing carbon. Proc Math Phys Eng Sci 2022. [DOI: 10.1098/rspa.2021.0580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Non-graphitizing carbons (NGCs) are an important class of solid carbons which cannot be converted into graphite by high-temperature heat treatment. They include commercially valuable materials such as activated carbon and glassy carbon. These carbons have been intensively studied for decades, but there is still no agreement about their detailed atomic structure, or the reasons for their resistance to graphitization. The first models for graphitizing and NGCs were proposed by Rosalind Franklin in the early 1950s, and while these are broadly correct, they are incomplete. Many alternative models of NGCs have been put forward since Franklin's time, but none has received universal acceptance. Diffraction and spectroscopic techniques can provide important insights into the nature of these carbons, but only direct microscopic imaging can reveal their true atomic structure. Here, we apply aberration-corrected transmission electron microscopy to an activated carbon prepared from waste biomass and present evidence for the presence of pentagonal and heptagonal carbon rings. This provides support for a model of the structure of NGC made up of curved fragments in which non-hexagonal rings are dispersed randomly throughout hexagonal networks.
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Affiliation(s)
- Christopher S. Allen
- Electron Physical Science Imaging Centre, Diamond Light Source Ltd., OX11 0DE, UK
- Department of Materials, University of Oxford, OX1 3PH, UK
| | - Fouad Ghamouss
- PCM2E, EA 6299 Université de Tours, Parc de Grandmont, 37200 Tours, France
- Materials Science and Nano-Engineering Department, Mohammed VI Polytechnic University, Hay Moulay Rachid, 43150 Ben Guerir, Morocco
| | - Ouassim Boujibar
- PCM2E, EA 6299 Université de Tours, Parc de Grandmont, 37200 Tours, France
| | - Peter J. F. Harris
- Electron Microscopy Laboratory, University of Reading, JJ Thomson Building, Whiteknights, Reading RG6 6AF, UK
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6
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Tiwari SK, Chen D, Chen Y, Thummavichai K, Ola O, Ma Z, Liu G, Wang N, Zhu Y. N-Doped Graphenelike Nanostructures from p-Nitro Aniline-Based Foam: Formation, Structure, and Applications as a Nanofiller. ACS OMEGA 2022; 7:3230-3239. [PMID: 35128236 PMCID: PMC8811766 DOI: 10.1021/acsomega.1c05139] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
Production of snake foam based on p-nitro aniline (PNA) was considered fun in old-school chemistry laboratories. Herein, we report the fabrication of a new carbon nanomaterial from PNA-based foam. The resulting material, resembling graphene and consisting of nitrogen heteroatoms, is N-doped graphenelike nanostructures, and their morphology, structure, and stability are comprehensively examined using combined techniques including C-13 NMR spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). An optimized route was also established for their large-scale production. Further experimental validation of them as a nanofiller in polymer [SEBS (20 wt %) and paraffin wax (80 wt %)]-based nanocomposites was carried out, and we found that the thermomechanical properties of the nanocomposites were synchronously improved, which was attributed to the enshrouding effect of the nanofiller to the polymer chains. Owing to their good thermomechanical property and low-cost feature, these new nanomaterials can be further explored as a promising candidate for applications in energy storage, catalysis, and CO2 capture.
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Affiliation(s)
- Santosh K. Tiwari
- Guangxi
Institute Fullerene Technology (GIFT), Key Laboratory of New Processing
Technology for Nonferrous Metals and Materials, Ministry of Education,
School of Resources, Environment and Materials, Guangxi University, Nanning 530000, China
- Department
of Chemistry, Warsaw University, Warsaw 00-927, Poland
| | - Ding Chen
- College
of Chemistry and Chemical Engineering, Guangxi
University, Nanning 530000, China
| | - Yu Chen
- College
of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4PY, U.K.
| | - Kunyapat Thummavichai
- College
of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4PY, U.K.
| | - Oluwafunmilola Ola
- Advanced
Materials Group, Faculty of Engineering, The University of Nottingham, Nottingham NG27 2RD, U.K.
| | - Zhiyuan Ma
- Guangxi
Institute Fullerene Technology (GIFT), Key Laboratory of New Processing
Technology for Nonferrous Metals and Materials, Ministry of Education,
School of Resources, Environment and Materials, Guangxi University, Nanning 530000, China
| | - Guangsheng Liu
- Guangxi
Institute Fullerene Technology (GIFT), Key Laboratory of New Processing
Technology for Nonferrous Metals and Materials, Ministry of Education,
School of Resources, Environment and Materials, Guangxi University, Nanning 530000, China
| | - Nannan Wang
- Guangxi
Institute Fullerene Technology (GIFT), Key Laboratory of New Processing
Technology for Nonferrous Metals and Materials, Ministry of Education,
School of Resources, Environment and Materials, Guangxi University, Nanning 530000, China
| | - Yanqiu Zhu
- Guangxi
Institute Fullerene Technology (GIFT), Key Laboratory of New Processing
Technology for Nonferrous Metals and Materials, Ministry of Education,
School of Resources, Environment and Materials, Guangxi University, Nanning 530000, China
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7
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Wen H, Xu X, Cheong S, Lo SC, Chen JH, Chang SLY, Dwyer C. Metrology of convex-shaped nanoparticles via soft classification machine learning of TEM images. NANOSCALE ADVANCES 2021; 3:6956-6964. [PMID: 36132371 PMCID: PMC9417281 DOI: 10.1039/d1na00524c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/11/2021] [Indexed: 06/15/2023]
Abstract
The shape of nanoparticles is a key performance parameter for many applications, ranging from nanophotonics to nanomedicines. However, the unavoidable shape variations, which occur even in precision-controlled laboratory synthesis, can significantly impact on the interpretation and reproducibility of nanoparticle performance. Here we have developed an unsupervised, soft classification machine learning method to perform metrology of convex-shaped nanoparticles from transmission electron microscopy images. Unlike the existing methods, which are based on hard classification, soft classification provides significantly greater flexibility in being able to classify both distinct shapes, as well as non-distinct shapes where hard classification fails to provide meaningful results. We demonstrate the robustness of our method on a range of nanoparticle systems, from laboratory-scale to mass-produced synthesis. Our results establish that the method can provide quantitative, accurate, and meaningful metrology of nanoparticle ensembles, even for ensembles entailing a continuum of (possibly irregular) shapes. Such information is critical for achieving particle synthesis control, and, more importantly, for gaining deeper understanding of shape-dependent nanoscale phenomena. Lastly, we also present a method, which we coin the "binary DoG", which achieves significant progress on the challenging problem of identifying the shapes of aggregated nanoparticles.
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Affiliation(s)
- Haotian Wen
- School of Materials Science and Engineering, University of New South Wales Sydney NSW 2052 Australia
| | - Xiaoxue Xu
- School of Mathematical and Physical Sciences, University of Technology, Sydney Ultimo NSW 2007 Australia
| | - Soshan Cheong
- Electron Microscope Unit, Mark Wainwright Analytical Centre, University of New South Wales Sydney NSW 2052 Australia
| | - Shen-Chuan Lo
- Material and Chemical Research Laboratories, Industrial Technology Research Institute Hsinchu Taiwan
| | - Jung-Hsuan Chen
- Material and Chemical Research Laboratories, Industrial Technology Research Institute Hsinchu Taiwan
| | - Shery L Y Chang
- School of Materials Science and Engineering, University of New South Wales Sydney NSW 2052 Australia
- Electron Microscope Unit, Mark Wainwright Analytical Centre, University of New South Wales Sydney NSW 2052 Australia
| | - Christian Dwyer
- Electron Imaging and Spectroscopy Tools PO Box 506 Sans Souci NSW 2219 Australia
- Physics, School of Science, RMIT University Melbourne Victoria 3001 Australia
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8
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Thiemann FL, Rowe P, Zen A, Müller EA, Michaelides A. Defect-Dependent Corrugation in Graphene. NANO LETTERS 2021; 21:8143-8150. [PMID: 34519502 DOI: 10.1021/acs.nanolett.1c02585] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Graphene's intrinsically corrugated and wrinkled topology fundamentally influences its electronic, mechanical, and chemical properties. Experimental techniques allow the manipulation of pristine graphene and the controlled production of defects which allows one to control the atomic out-of-plane fluctuations and thus tune graphene's properties. Here, we perform large scale machine learning-driven molecular dynamics simulations to understand the impact of defects on the structure of graphene. We find that defects cause significantly higher corrugation leading to a strongly wrinkled surface. The magnitude of this structural transformation strongly depends on the defect concentration and specific type of defect. Analyzing the atomic neighborhood of the defects reveals that the extent of these morphological changes depends on the preferred geometrical orientation and the interactions between defects. While our work highlights that defects can strongly affect graphene's morphology, it also emphasizes the differences between distinct types by linking the global structure to the local environment of the defects.
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Affiliation(s)
- Fabian L Thiemann
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Patrick Rowe
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Andrea Zen
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Dipartimento di Fisica Ettore Pancini, Università di Napoli Federico II, Monte S. Angelo, I-80126 Napoli, Italy
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Erich A Müller
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Angelos Michaelides
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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9
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Prismatic 2.0 - Simulation software for scanning and high resolution transmission electron microscopy (STEM and HRTEM). Micron 2021; 151:103141. [PMID: 34560356 DOI: 10.1016/j.micron.2021.103141] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/20/2021] [Accepted: 08/22/2021] [Indexed: 11/22/2022]
Abstract
Scanning transmission electron microscopy (STEM), where a converged electron probe is scanned over a sample's surface and an imaging, diffraction, or spectroscopic signal is measured as a function of probe position, is an extremely powerful tool for materials characterization. The widespread adoption of hardware aberration correction, direct electron detectors, and computational imaging methods have made STEM one of the most important tools for atomic-resolution materials science. Many of these imaging methods rely on accurate imaging and diffraction simulations in order to interpret experimental results. However, STEM simulations have traditionally required large calculation times, as modeling the electron scattering requires a separate simulation for each of the typically millions of probe positions. We have created the Prismatic simulation code for fast simulation of STEM experiments with support for multi-CPU and multi-GPU (graphics processing unit) systems, using both the conventional multislice and our recently-introduced PRISM method. In this paper, we introduce Prismatic version 2.0, which adds many new algorithmic improvements, an updated graphical user interface (GUI), post-processing of simulation data, and additional operating modes such as plane-wave TEM. We review various aspects of the simulation methods and codes in detail and provide various simulation examples. Prismatic 2.0 is freely available both as an open-source package that can be run using a C++ or Python command line interface, or GUI, as well within a Docker container environment.
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10
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Sadre R, Ophus C, Butko A, Weber GH. Deep Learning Segmentation of Complex Features in Atomic-Resolution Phase-Contrast Transmission Electron Microscopy Images. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:804-814. [PMID: 34353384 DOI: 10.1017/s1431927621000167] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Phase-contrast transmission electron microscopy (TEM) is a powerful tool for imaging the local atomic structure of materials. TEM has been used heavily in studies of defect structures of two-dimensional materials such as monolayer graphene due to its high dose efficiency. However, phase-contrast imaging can produce complex nonlinear contrast, even for weakly scattering samples. It is, therefore, difficult to develop fully automated analysis routines for phase-contrast TEM studies using conventional image processing tools. For automated analysis of large sample regions of graphene, one of the key problems is segmentation between the structure of interest and unwanted structures such as surface contaminant layers. In this study, we compare the performance of a conventional Bragg filtering method with a deep learning routine based on the U-Net architecture. We show that the deep learning method is more general, simpler to apply in practice, and produces more accurate and robust results than the conventional algorithm. We provide easily adaptable source code for all results in this paper and discuss potential applications for deep learning in fully automated TEM image analysis.
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Affiliation(s)
- Robbie Sadre
- Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA94720, USA
| | - Colin Ophus
- NCEM, Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA94720, USA
| | - Anastasiia Butko
- Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA94720, USA
| | - Gunther H Weber
- Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA94720, USA
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11
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Zhang X, Wang S. Interfacial Strengthening of Graphene/Aluminum Composites through Point Defects: A First-Principles Study. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:738. [PMID: 33804166 PMCID: PMC8001873 DOI: 10.3390/nano11030738] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 11/19/2022]
Abstract
The relationship between point defects and mechanical properties has not been fully understood yet from a theoretical perspective. This study systematically investigated how the Stone-Wales (SW) defect, the single vacancy (SV), and the double vacancy (DV) affect the mechanical properties of graphene/aluminum composites. The interfacial bonding energies containing the SW and DV defects were about twice that of the pristine graphene. Surprisingly, the interfacial bonding energy of the composites with single vacancy was almost four times that of without defect in graphene. These results indicate that point defects enhance the interfacial bonding strength significantly and thus improve the mechanical properties of graphene/aluminum composites, especially the SV defect. The differential charge density elucidates that the formation of strong Al-C covalent bonds at the defects is the most fundamental reason for improving the mechanical properties of graphene/aluminum composites. The theoretical research results show the defective graphene as the reinforcing phase is more promising to be used in the metal matrix composites, which will provide a novel design guideline for graphene reinforced metal matrix composites. Furthermore, the sp3-hybridized C dangling bonds increase the chemical activity of the SV graphene, making it possible for the SV graphene/aluminum composites to be used in the catalysis field.
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Affiliation(s)
- Xin Zhang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China;
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Shaoqing Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China;
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12
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Islam A, Mukherjee B, Pandey KK, Keshri AK. Ultra-Fast, Chemical-Free, Mass Production of High Quality Exfoliated Graphene. ACS NANO 2021; 15:1775-1784. [PMID: 33448799 DOI: 10.1021/acsnano.0c09451] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
As graphene penetrates into industries, it is essential to mass produce high quality graphene sheets. New discoveries face formidable challenges in the marketplace due to the lack of proficient protocols to produce graphene on a commercial scale while maintaining its quality. Here, we present a conspicuous protocol for ultrafast exfoliation of graphite into high quality graphene on the sub-kilogram scale without the use of any intercalants, chemicals, or solvent. We show that graphite can be exfoliated using a plasma spray technique with high single-layer selectivity (∼85%) at a very high production rate (48 g/h). This is possible because of the inherent characteristics of the protocol which provides sudden thermal shock followed by two-stage shear. The exfoliated graphene shows almost no basal defect (Id/Ig: 0) and possesses high quality (C/O ratio: 21.2, sp2 %: ∼95%), an indication of negligible structural deterioration. The results were reproducible indicating the adeptness of the protocol. We provided several proofs-of-concept of plasma spray exfoliated graphene to demonstrate its utility in applications such as mechanical reinforcements; frictionless, transparent conductive coatings; and energy storage devices.
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Affiliation(s)
- Aminul Islam
- Plasma Spray Coating Laboratory, Metallurgical and Materials Engineering Indian Institute of Technology Patna, Bihar-801106, India
| | - Biswajyoti Mukherjee
- Plasma Spray Coating Laboratory, Metallurgical and Materials Engineering Indian Institute of Technology Patna, Bihar-801106, India
| | - Krishna Kant Pandey
- Plasma Spray Coating Laboratory, Metallurgical and Materials Engineering Indian Institute of Technology Patna, Bihar-801106, India
| | - Anup Kumar Keshri
- Plasma Spray Coating Laboratory, Metallurgical and Materials Engineering Indian Institute of Technology Patna, Bihar-801106, India
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13
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Parent LR, Gnanasekaran K, Korpanty J, Gianneschi NC. 100th Anniversary of Macromolecular Science Viewpoint: Polymeric Materials by In Situ Liquid-Phase Transmission Electron Microscopy. ACS Macro Lett 2021; 10:14-38. [PMID: 35548998 DOI: 10.1021/acsmacrolett.0c00595] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A century ago, Hermann Staudinger proposed the macromolecular theory of polymers, and now, as we enter the second century of polymer science, we face a different set of opportunities and challenges for the development of functional soft matter. Indeed, many fundamental questions remain open, relating to physical structures and mechanisms of phase transformations at the molecular and nanoscale. In this Viewpoint, we describe efforts to develop a dynamic, in situ microscopy tool suited to the study of polymeric materials at the nanoscale that allows for direct observation of discrete structures and processes in solution, as a complement to light, neutron, and X-ray scattering methods. Liquid-phase transmission electron microscopy (LPTEM) is a nascent in situ imaging technique for characterizing and examining solvated nanomaterials in real time. Though still under development, LPTEM has been shown to be capable of several modes of imaging: (1) imaging static solvated materials analogous to cryo-TEM, (2) videography of nanomaterials in motion, (3) observing solutions or nanomaterials undergoing physical and chemical transformations, including synthesis, assembly, and phase transitions, and (4) observing electron beam-induced chemical-materials processes. Herein, we describe opportunities and limitations of LPTEM for polymer science. We review the basic experimental platform of LPTEM and describe the origin of electron beam effects that go hand in hand with the imaging process. These electron beam effects cause perturbation and damage to the sample and solvent that can manifest as artefacts in images and videos. We describe sample-specific experimental guidelines and outline approaches to mitigate, characterize, and quantify beam damaging effects. Altogether, we seek to provide an overview of this nascent field in the context of its potential to contribute to the advancement of polymer science.
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Affiliation(s)
- Lucas R. Parent
- Innovation Partnership Building, The University of Connecticut, Storrs, Connecticut 06269, United States
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14
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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.
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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
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15
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Tsai YJ, Kuo CL. Effect of Structural Disorders on the Li Storage Capacity of Graphene Nanomaterials: A First-Principles Study. ACS APPLIED MATERIALS & INTERFACES 2020; 12:22917-22929. [PMID: 32352275 DOI: 10.1021/acsami.0c04188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We employed first-principles calculations to investigate the effect of structural disorders on the Li storage capacity of graphene nanomaterials. Our calculations first revealed that the Li storage capacity of a graphene monolayer does not necessarily increase with the size of a C vacancy created but is largely determined by the local geometry of the defect sites. Our electronic structure analysis further revealed that the enhanced Li storage capacity by the C vacancy defect is mainly attributed to the increased number of the unoccupied electronic density of states lying near the Fermi level, which can be substantially increased by raising the number of bond rotations within the vacancy sites. Furthermore, it was also found that the Li storage capacity of graphene can be effectively enhanced by increasing the degree of local ring disorders without the presence of any vacancy defect. The amorphous graphene structure was shown to possess a relatively higher Li storage capacity compared to pristine graphene, primarily owing to the presence of many nonhexagonal rings randomly distributed in the graphene lattice. These nonhexagonal rings can create many electron-deficient regions on the graphene surface to effectively accommodate more electrons from Li, thereby substantially enhancing the Li storage capacity of graphene nanomaterials.
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Affiliation(s)
- Yu-Jen Tsai
- Department of Materials Science and Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan
| | - Chin-Lung Kuo
- Department of Materials Science and Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan
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16
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Tade RS, Nangare SN, Patil AG, Pandey A, Deshmukh PK, Patil DR, Agrawal TN, Mutalik S, Patil AM, More MP, Bari SB, Patil PO. Recent Advancement in Bio-precursor derived graphene quantum dots: Synthesis, Characterization and Toxicological Perspective. NANOTECHNOLOGY 2020; 31:292001. [PMID: 32176876 DOI: 10.1088/1361-6528/ab803e] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Graphene quantum dots (GQDs), impressive materials with enormous future potential, are reviewed from their inception, including different precursors. Considering the increasing burden of industrial and ecological bio-waste, there is an urgency to develop techniques which will convert biowaste into active moieties of interest. Amongst the various materials explored, we selectively highlight the use of potential carbon containing bioprecursors (e.g. plant-based, amino acids, carbohydrates), and industrial waste and its conversion into GQDs with negligible use of chemicals. This review focuses on the effects of different processing parameters that affect the properties of GQDs, including the surface functionalization, paradigmatic characterization, toxicity and biocompatibility issues of bioprecursor derived GQDs. This review also examines current challenges and s the ongoing exploration of potential bioprecursors for ecofriendly GQD synthesis for future applications. This review sheds further light on the electronic and optical properties of GQDs along with the effects of doping on the same. This review may aid in future design approaches and applications of GQDs in the biomedical and materials design fields.
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Affiliation(s)
- Rahul S Tade
- H R Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra 425405, India
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17
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Park HJ, Cha J, Choi M, Kim JH, Tay RY, Teo EHT, Park N, Hong S, Lee Z. One-dimensional hexagonal boron nitride conducting channel. SCIENCE ADVANCES 2020; 6:eaay4958. [PMID: 32181347 PMCID: PMC7060069 DOI: 10.1126/sciadv.aay4958] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 12/12/2019] [Indexed: 05/16/2023]
Abstract
Hexagonal boron nitride (hBN) is an insulating two-dimensional (2D) material with a large bandgap. Although known for its interfacing with other 2D materials and structural similarities to graphene, the potential use of hBN in 2D electronics is limited by its insulating nature. Here, we report atomically sharp twin boundaries at AA'/AB stacking boundaries in chemical vapor deposition-synthesized few-layer hBN. We find that the twin boundary is composed of a 6'6' configuration, showing conducting feature with a zero bandgap. Furthermore, the formation mechanism of the atomically sharp twin boundaries is suggested by an analogy with stacking combinations of AA'/AB based on the observations of extended Klein edges at the layer boundaries of AB-stacked hBN. The atomically sharp AA'/AB stacking boundary is promising as an ultimate 1D electron channel embedded in insulating pristine hBN. This study will provide insights into the fabrication of single-hBN electronic devices.
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Affiliation(s)
- Hyo Ju Park
- School of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
| | - Janghwan Cha
- Department of Physics, Graphene Research Institute, and GRI-TPC International Research Center, Sejong University, Seoul 05006, Republic of Korea
| | - Min Choi
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Jung Hwa Kim
- School of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Roland Yingjie Tay
- School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
- Temasek Laboratories@NTU, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Edwin Hang Tong Teo
- School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Noejung Park
- Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Suklyun Hong
- Department of Physics, Graphene Research Institute, and GRI-TPC International Research Center, Sejong University, Seoul 05006, Republic of Korea
- Corresponding author. (Z.L.); (S.H.)
| | - Zonghoon Lee
- School of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
- Corresponding author. (Z.L.); (S.H.)
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18
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Raman spectroscopy and transmission electron microscopy of long linear atomic carbon chains generated by field electron emission accompanied with electrical discharge of carbon nanotube films. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-0481-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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19
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Skowron ST, Roberts SL, Khlobystov AN, Besley E. The effects of encapsulation on damage to molecules by electron radiation. Micron 2019; 120:96-103. [PMID: 30818248 DOI: 10.1016/j.micron.2019.02.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 02/16/2019] [Accepted: 02/19/2019] [Indexed: 10/27/2022]
Abstract
Encapsulation of materials imaged by high resolution transmission electron microscopy presents a promising route to the reduction of sample degradation, both independently and in combination with other traditional solutions to controlling radiation damage. In bulk crystals, the main effect of encapsulation (or coating) is the elimination of diffusion routes of beam-induced radical species, enhancing recombination rates and acting to limit overall damage. Moving from bulk to low dimensional materials has significant effects on the nature of damage under the electron beam. We consider the major changes in mechanisms of damage of low dimensional materials by separating the effects of dimensional reduction from the effects of encapsulation. An effect of confinement is discussed using a model example of coronene molecules encapsulated inside single walled carbon nanotubes as determined from molecular dynamics simulations calculating the threshold energy required for hydrogen atom dissociation. The same model system is used to estimate the rate at which the nanotube can dissipate excess thermal energy above room temperature by acting as a thermal sink.
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Affiliation(s)
- Stephen T Skowron
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Sarah L Roberts
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Andrei N Khlobystov
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Elena Besley
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
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20
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Azhagiya Singam ER, Zhang Y, Magnin G, Miranda-Carvajal I, Coates L, Thakkar R, Poblete H, Comer J. Thermodynamics of Adsorption on Graphenic Surfaces from Aqueous Solution. J Chem Theory Comput 2018; 15:1302-1316. [DOI: 10.1021/acs.jctc.8b00830] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- E. R. Azhagiya Singam
- Institute of Computational Comparative Medicine, Nanotechnology Innovation Center of Kansas State, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, United States
| | - Yuntao Zhang
- Institute of Computational Comparative Medicine, Nanotechnology Innovation Center of Kansas State, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, United States
| | - Geraldine Magnin
- Institute of Computational Comparative Medicine, Nanotechnology Innovation Center of Kansas State, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, United States
| | - Ingrid Miranda-Carvajal
- Universidad Nacional de Colombia, sede Bogotá, Facultad de Ciencias, Departamento de Química, Carrera 30 No. 45-03, Bogotá 111321, Colombia
| | - Logan Coates
- Institute of Computational Comparative Medicine, Nanotechnology Innovation Center of Kansas State, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, United States
| | - Ravindra Thakkar
- Institute of Computational Comparative Medicine, Nanotechnology Innovation Center of Kansas State, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, United States
| | - Horacio Poblete
- Center for Bioinformatics and Molecular Simulation, Facultad de Ingeniería, Nucleo Científico Multidiciplinario-DI, Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Talca, 3460000 Talca, Chile
| | - Jeffrey Comer
- Institute of Computational Comparative Medicine, Nanotechnology Innovation Center of Kansas State, Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, United States
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21
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Affiliation(s)
| | - Philippe Serp
- LCC CNRS-UPR 8241 ENSIACET Université de Toulouse Toulouse France
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22
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Electrochemical Performance of Few-Layer Graphene Nano-Flake Supercapacitors Prepared by the Vacuum Kinetic Spray Method. COATINGS 2018. [DOI: 10.3390/coatings8090302] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A few-layer graphene nano-flake thin film was prepared by an affordable vacuum kinetic spray method at room temperature and modest low vacuum conditions. In this economical approach, graphite microparticles, a few layers thick, are deposited on a stainless-steel substrate to form few-layer graphene nano-flakes using a nanoparticle deposition system (NPDS). The NPDS allows for a large area deposition at a low cost and can deposit various metal oxides at room temperature and low vacuum conditions. The morphology and structure of the deposited thin films are alterable by changing the scan speed of the deposition. These changes were verified by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy. The electrochemical performances of the supercapacitors, fabricated using the deposited films and H3PO4–PVA gel electrolytes with different concentrations, were measured using a 2-electrode cell. The electrochemical performance was evaluated by cyclic voltammetry, galvanostatic Charge–discharge, and electrochemical impedance spectroscopy. The proposed affordable fabricated supercapacitors show a high areal capacitance and a small equivalent series resistance.
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23
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Abbasian M, Roudi MM, Mahmoodzadeh F, Eskandani M, Jaymand M. Chitosan-grafted-poly(methacrylic acid)/graphene oxide nanocomposite as a pH-responsive de novo cancer chemotherapy nanosystem. Int J Biol Macromol 2018; 118:1871-1879. [PMID: 30017982 DOI: 10.1016/j.ijbiomac.2018.07.036] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/28/2018] [Accepted: 07/10/2018] [Indexed: 01/23/2023]
Abstract
The aim of this study was the design and development of a novel de novo drug delivery system for cancer chemotherapy. For this purpose, chitosan (CS) functionalized using phthalic anhydride followed by 4-cyano, 4-[(phenylcarbothioyl) sulfanyl] pentanoic acid as a chain transfer agent (CTA) to afford CS-CTA macroinitiator. The synthesized CS-CTA macroinitiator was then copolymerized with methacrylic acid (MAA) monomer using reversible addition-fragmentation chain transfer (RAFT) polymerization technique to produce chitosan-graft-poly(methacrylic acid) (CS-g-PMAA) graft copolymer. Afterward, graphene oxide (GO) nanosheets were incorporated into the synthesized copolymer through the physical interactions. The CS-g-PMAA/GO nanocomposite was loaded with doxorubicin hydrochloride (DOX) as a universal anticancer drug. The biocompatibility, DOX-loading capacity, and pH dependent drug release behavior of the developed nanocomposite were also investigated. As the experimental results, as well as superior biological and physicochemical features of CS and GO, we envision that the developed CS-g-PMAA/GO nanocomposite may be applied as de novo drug delivery nanosystem for cancer chemotherapy.
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Affiliation(s)
- Mojtaba Abbasian
- Department of Chemistry, Payame Noor University, P.O. BOX: 19395-3697, Tehran, Iran
| | - Mohammad-Mahdi Roudi
- Department of Polymer, Faculty of Engineering, University of Bonab, P.O. Box: 55517, Bonab, Iran
| | | | - Morteza Eskandani
- Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, P.O. BOX: 51656-65811, Tabriz, Iran
| | - Mehdi Jaymand
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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24
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TEM Nano-Moiré Pattern Analysis of a Copper/Single Walled Carbon Nanotube Nanocomposite Synthesized by Laser Surface Implanting. C — JOURNAL OF CARBON RESEARCH 2018. [DOI: 10.3390/c4010019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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25
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Oxidation behavior of graphene-coated copper at intrinsic graphene defects of different origins. Nat Commun 2017; 8:1549. [PMID: 29147017 PMCID: PMC5691087 DOI: 10.1038/s41467-017-01814-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 10/18/2017] [Indexed: 11/08/2022] Open
Abstract
The development of ultrathin barrier films is vital to the advanced semiconductor industry. Graphene appears to hold promise as a protective coating; however, the polycrystalline and defective nature of engineered graphene hinders its practical applications. Here, we investigate the oxidation behavior of graphene-coated Cu foils at intrinsic graphene defects of different origins. Macro-scale information regarding the spatial distribution and oxidation resistance of various graphene defects is readily obtained using optical and electron microscopies after the hot-plate annealing. The controlled oxidation experiments reveal that the degree of structural deficiency is strongly dependent on the origins of the structural defects, the crystallographic orientations of the underlying Cu grains, the growth conditions of graphene, and the kinetics of the graphene growth. The obtained experimental and theoretical results show that oxygen radicals, decomposed from water molecules in ambient air, are effectively inverted at Stone–Wales defects into the graphene/Cu interface with the assistance of facilitators. Graphene holds promise as a protective coating; however, lattice defects may hinder its practical applicability. Here, the authors investigate the oxidation behavior of graphene-coated copper foils and unveil the interplay between structural defects and oxygen radicals from water molecules in ambient air.
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26
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Zhang H, Wen H, Liu Z, Zhang Q, Xie H. TEM nano-Moiré evaluation for an invisible lattice structure near the grain interface. NANOSCALE 2017; 9:15923-15933. [PMID: 29019497 DOI: 10.1039/c7nr04262k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Moiré technique is a powerful, important and effective tool for scientific research, from the nano-scale to the macro-scale, which is essentially the interference between two or more periodic structures with a similar frequency. In this study, an inverse transmission electron microscopy (TEM) nano-Moiré method has been proposed, for the first time, to reconstruct an invisible lattice structure near the grain interface, where only one kind of lattice structure and Moiré fringe were visible in a high resolution TEM (HRTEM) image simultaneously. The inversion process was performed in detail. Three rules were put forward to ensure the uniqueness of the inversion result. The HRTEM image of a top-coat/thermally grown oxide interface in a thermal barrier coating (TBC) structure was observed with coexisting visible lattice and Moiré fringes. Using the inverse TEM nano-Moiré method, the invisible lower layer lattice was inversed and a 3-dimensional structure near the interface was also reconstructed to some degree. The real strain field of oriented invisible and visible lattices and the relative strain field of the Moiré fringe in the grain and near the grain boundary were obtained simultaneously through the subset geometric phase analysis method. The possible failure mechanism and position of the TBC spallation from the nano-scale to the micro-scale were discussed.
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Affiliation(s)
- Hongye Zhang
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China.
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27
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Lei J, Hu Y, Liu Z, Cheng GJ, Zhao K. Defects Mediated Corrosion in Graphene Coating Layer. ACS APPLIED MATERIALS & INTERFACES 2017; 9:11902-11908. [PMID: 28318224 DOI: 10.1021/acsami.7b01539] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mixed results were reported on the anticorrosion of graphene-coated metal surfaces-while graphene serves as an effective short-term barrier against corrosion and oxidation due to its low permeability to gases, the galvanic cell between graphene and the metal substrate facilitates extensive corrosion in the long run. Defects in the graphene layer provide pathways for the permeation of oxidizing species. We study the role of defects in graphene in the anticorrosion using first-principles theoretical modeling. Experiments in the highly reactive environment indicate that the oxidized products primarily distribute along the grain boundaries of graphene. We analyze the thermodynamics of the absorption of S and O on the grain boundaries of graphene on the basis of density functional theory. The insertion of S and O at the vacancy sites is energetically favorable. The interstitial impurities facilitate structural transformation of graphene and significantly decrease the mechanical strength of the graphene layer. Furthermore, the presence of the interstitial S and O reduces the chemical stability of graphene by enhancing the formation of vacancies and promoting dispersive growth of corrosive reactants along the grain boundaries.
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Affiliation(s)
- Jincheng Lei
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University , Xi'an 710049, China
| | | | - Zishun Liu
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University , Xi'an 710049, China
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28
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Nguyen L, Komsa HP, Khestanova E, Kashtiban RJ, Peters JJP, Lawlor S, Sanchez AM, Sloan J, Gorbachev RV, Grigorieva IV, Krasheninnikov AV, Haigh SJ. Atomic Defects and Doping of Monolayer NbSe 2. ACS NANO 2017; 11:2894-2904. [PMID: 28195699 DOI: 10.1021/acsnano.6b08036] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We have investigated the structure of atomic defects within monolayer NbSe2 encapsulated in graphene by combining atomic resolution transmission electron microscope imaging, density functional theory (DFT) calculations, and strain mapping using geometric phase analysis. We demonstrate the presence of stable Nb and Se monovacancies in monolayer material and reveal that Se monovacancies are the most frequently observed defects, consistent with DFT calculations of their formation energy. We reveal that adventitious impurities of C, N, and O can substitute into the NbSe2 lattice stabilizing Se divacancies. We further observe evidence of Pt substitution into both Se and Nb vacancy sites. This knowledge of the character and relative frequency of different atomic defects provides the potential to better understand and control the unusual electronic and magnetic properties of this exciting two-dimensional material.
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Affiliation(s)
| | | | | | - Reza J Kashtiban
- Department of Physics, University of Warwick , Coventry, CV4 7AL, United Kingdom
| | - Jonathan J P Peters
- Department of Physics, University of Warwick , Coventry, CV4 7AL, United Kingdom
| | | | - Ana M Sanchez
- Department of Physics, University of Warwick , Coventry, CV4 7AL, United Kingdom
| | - Jeremy Sloan
- Department of Physics, University of Warwick , Coventry, CV4 7AL, United Kingdom
| | | | | | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf , 01328 Dresden, Germany
- National University of Science and Technology MISiS , Leninskiy Prospekt, Moscow, 119049, Russian Federation
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29
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Lee HC, Liu WW, Chai SP, Mohamed AR, Aziz A, Khe CS, Hidayah NS, Hashim U. Review of the synthesis, transfer, characterization and growth mechanisms of single and multilayer graphene. RSC Adv 2017. [DOI: 10.1039/c7ra00392g] [Citation(s) in RCA: 214] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Graphene has emerged as the most popular topic in the active research field since graphene's discovery in 2004 by Andrei Geim and Kostya Novoselov.
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Affiliation(s)
- H. Cheun Lee
- Institute of Nano Electronic Engineering
- Universiti Malaysia Perlis
- 01000 Kangar
- Malaysia
| | - Wei-Wen Liu
- Institute of Nano Electronic Engineering
- Universiti Malaysia Perlis
- 01000 Kangar
- Malaysia
| | | | - Abdul Rahman Mohamed
- School of Chemical Engineering
- Engineering Campus
- Universiti Sains Malaysia
- 14300 Nibong Tebal
- Malaysia
| | - Azizan Aziz
- School of Material and Mineral Resources Engineering
- Engineering Campus
- Universiti Sains Malaysia
- 14300 Nibong Tebal
- Malaysia
| | - Cheng-Seong Khe
- Department of Fundamental and Applied Sciences
- Universiti Teknologi PETRONAS
- Bandar Seri Iskandar
- Malaysia
| | - N. M. S. Hidayah
- Institute of Nano Electronic Engineering
- Universiti Malaysia Perlis
- 01000 Kangar
- Malaysia
| | - U. Hashim
- Institute of Nano Electronic Engineering
- Universiti Malaysia Perlis
- 01000 Kangar
- Malaysia
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30
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Baeza A, Castillo RR, Torres-Pardo A, González-Calbet JM, Vallet-Regí M. Electron microscopy for inorganic-type drug delivery nanocarriers for antitumoral applications: what does it reveal? J Mater Chem B 2017; 5:2714-2725. [DOI: 10.1039/c6tb03062a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electron microscopy applied to the development of inorganic nanoparticles for clinical applications.
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Affiliation(s)
- A. Baeza
- Dpto. Química Inorgánica y Bioinorgánica
- Facultad de Farmacia
- Universidad Complutense de Madrid
- Plaza Ramon y Cajal s/n
- Instituto de Investigación Sanitaria Hospital 12 de Octubre i + 12
| | - R. R. Castillo
- Dpto. Química Inorgánica y Bioinorgánica
- Facultad de Farmacia
- Universidad Complutense de Madrid
- Plaza Ramon y Cajal s/n
- Instituto de Investigación Sanitaria Hospital 12 de Octubre i + 12
| | - A. Torres-Pardo
- Dpto. de Química Inorgánica Facultad de Químicas
- Universidad Complutense de Madrid
- Madrid
- Spain
| | - J. M. González-Calbet
- Dpto. de Química Inorgánica Facultad de Químicas
- Universidad Complutense de Madrid
- Madrid
- Spain
| | - M. Vallet-Regí
- Dpto. Química Inorgánica y Bioinorgánica
- Facultad de Farmacia
- Universidad Complutense de Madrid
- Plaza Ramon y Cajal s/n
- Instituto de Investigación Sanitaria Hospital 12 de Octubre i + 12
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31
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Sharma S, Prakash V, Mehta S. Graphene/silver nanocomposites-potential electron mediators for proliferation in electrochemical sensing and SERS activity. Trends Analyt Chem 2017. [DOI: 10.1016/j.trac.2016.10.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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32
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Ophus C, Rasool HI, Linck M, Zettl A, Ciston J. Automatic software correction of residual aberrations in reconstructed HRTEM exit waves of crystalline samples. ACTA ACUST UNITED AC 2016; 2:15. [PMID: 28003952 PMCID: PMC5127900 DOI: 10.1186/s40679-016-0030-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 11/24/2016] [Indexed: 11/29/2022]
Abstract
We develop an automatic and objective method to measure and correct residual aberrations in atomic-resolution HRTEM complex exit waves for crystalline samples aligned along a low-index zone axis. Our method uses the approximate rotational point symmetry of a column of atoms or single atom to iteratively calculate a best-fit numerical phase plate for this symmetry condition, and does not require information about the sample thickness or precise structure. We apply our method to two experimental focal series reconstructions, imaging a β-Si3N4 wedge with O and N doping, and a single-layer graphene grain boundary. We use peak and lattice fitting to evaluate the precision of the corrected exit waves. We also apply our method to the exit wave of a Si wedge retrieved by off-axis electron holography. In all cases, the software correction of the residual aberration function improves the accuracy of the measured exit waves.
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Affiliation(s)
- Colin Ophus
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, USA
| | - Haider I Rasool
- Department of Physics, University of California Berkeley, 366 LeConte Hall, Berkeley, MC 7300 USA ; Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, USA
| | - Martin Linck
- Corrected Electron Optical Systems GmbH, Englerstrasse 28, 69126 Heidelberg, Germany
| | - Alex Zettl
- Department of Physics, University of California Berkeley, 366 LeConte Hall, Berkeley, MC 7300 USA ; Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, USA
| | - Jim Ciston
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, USA
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33
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Robertson AW, Lin YC, Wang S, Sawada H, Allen CS, Chen Q, Lee S, Lee GD, Lee J, Han S, Yoon E, Kirkland AI, Kim H, Suenaga K, Warner JH. Atomic Structure and Spectroscopy of Single Metal (Cr, V) Substitutional Dopants in Monolayer MoS 2. ACS NANO 2016; 10:10227-10236. [PMID: 27934090 DOI: 10.1021/acsnano.6b05674] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Dopants in two-dimensional dichalcogenides have a significant role in affecting electronic, mechanical, and interfacial properties. Controllable doping is desired for the intentional modification of such properties to enhance performance; however, unwanted defects and impurity dopants also have a detrimental impact, as often found for chemical vapor deposition (CVD) grown films. The reliable identification, and subsequent characterization, of dopants is therefore of significant importance. Here, we show that Cr and V impurity atoms are found in CVD grown MoS2 monolayer 2D crystals as single atom substitutional dopants in place of Mo. We attribute these impurities to trace elements present in the MoO3 CVD precursor. Simultaneous annular dark field scanning transmission electron microscopy (ADF-STEM) and electron energy loss spectroscopy (EELS) is used to map the location of metal atom substitutions of Cr and V in MoS2 monolayers with single atom precision. The Cr and V are stable under electron irradiation at 60 to 80 kV, when incorporated into line defects, and when heated to elevated temperatures. The combined ADF-STEM and EELS differentiates these Cr and V dopants from other similar contrast defect structures, such as 2S self-interstitials at the Mo site, preventing misidentification. Density functional theory calculations reveal that the presence of Cr or V causes changes to the density of states, indicating doping of the MoS2 material. These transferred impurities could help explain the presence of trapped charges in CVD prepared MoS2.
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Affiliation(s)
- Alex W Robertson
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Yung-Chang Lin
- Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , AIST Central 5, Tsukuba 305-8564, Japan
| | - Shanshan Wang
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Hidetaka Sawada
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
- JEOL Limited, 3-1-2 Musashino, Akishima, Tokyo 196-8558, Japan
- Electron Physical Sciences Imaging Center, Diamond Light Source Limited, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Christopher S Allen
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
- Electron Physical Sciences Imaging Center, Diamond Light Source Limited, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Qu Chen
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Sungwoo Lee
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Gun-Do Lee
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Joohee Lee
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Seungwu Han
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - 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
- Electron Physical Sciences Imaging Center, Diamond Light Source Limited, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Heeyeon Kim
- Convergence Materials Laboratory, Korea Institute of Energy Research , 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Korea
| | - Kazu Suenaga
- Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , AIST Central 5, Tsukuba 305-8564, Japan
| | - Jamie H Warner
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
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34
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Varenik M, Green MJ, Regev O. Distinguishing Self-Assembled Pyrene Structures from Exfoliated Graphene. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:10699-10704. [PMID: 27723350 DOI: 10.1021/acs.langmuir.6b03379] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sonication-assisted graphene production from graphite is a popular lab-scale approach in which ultrasound energy breaks down graphite sheets into graphene flakes in aqueous medium. Dispersants (surfactant molecules) are incorporated into the solution to prevent individual graphene flakes from reaggregating. However, in solution these dispersants self-assemble into various structures, which can interfere with the characterization of the graphene produced. In this study, we characterized graphene dispersions stabilized by a family of pyrene-based surfactants that facilitate a high exfoliation yield. These surfactants self-assembled to form flakes and ribbons-shapes very similar to those of graphene structures. The dispersant structures were present both in the graphene dispersion and in the precipitate after the solvent had been evaporated and could therefore have been mistakenly identified as graphene by electron microscopy techniques and other characterization techniques, such as Raman and X-ray photoelectron spectroscopy. Contrary to previous reports, we showed-by removing the dispersants by filtration and washing-that the surfactants did not affect the shape of the graphene prepared by sonication.
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Affiliation(s)
| | - Micah J Green
- Artie McFerrin Department of Chemical Engineering, Texas A&M University , College Station, Texas 77843-3122, United States
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35
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Gong C, Robertson AW, He K, Lee GD, Yoon E, Allen CS, Kirkland AI, Warner JH. Thermally Induced Dynamics of Dislocations in Graphene at Atomic Resolution. ACS NANO 2015; 9:10066-10075. [PMID: 26461042 DOI: 10.1021/acsnano.5b05355] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Thermally induced dislocation movements are important in understanding the effects of high temperature annealing on modifying the crystal structure. We use an in situ heating holder in an aberration corrected transmission electron microscopy to study the movement of dislocations in suspended monolayer graphene up to 800 °C. Control of temperature enables the differentiation of electron beam induced effects and thermally driven processes. At room temperature, the dynamics of dislocation behavior is driven by the electron beam irradiation at 80 kV; however at higher temperatures, increased movement of the dislocation is observed and provides evidence for the influence of thermal energy to the system. An analysis of the dislocation movement shows both climb and glide processes, including new complex pathways for migration and large nanoscale rapid jumps between fixed positions in the lattice. The improved understanding of the high temperature dislocation movement provides insights into annealing processes in graphene and the behavior of defects with increased heat.
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Affiliation(s)
- Chuncheng Gong
- 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
| | - Gun-Do Lee
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Euijoon Yoon
- Department of Materials Science and Engineering, Seoul National University , Seoul 151-742, Korea
| | - Christopher S Allen
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Angus I Kirkland
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
| | - Jamie H Warner
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
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36
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La Torre A, Botello-Mendez A, Baaziz W, Charlier JC, Banhart F. Strain-induced metal-semiconductor transition observed in atomic carbon chains. Nat Commun 2015; 6:6636. [PMID: 25818506 PMCID: PMC4389248 DOI: 10.1038/ncomms7636] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 02/09/2015] [Indexed: 12/25/2022] Open
Abstract
Carbyne, the sp(1)-hybridized phase of carbon, is still a missing link in the family of carbon allotropes. While the bulk phases of carbyne remain elusive, the elementary constituents, that is, linear chains of carbon atoms, have already been observed using the electron microscope. Isolated atomic chains are highly interesting one-dimensional conductors that have stimulated considerable theoretical work. Experimental information, however, is still very limited. Here we show electrical measurements and first-principles transport calculations on monoatomic carbon chains. When the 1D system is under strain, the chains are semiconducting corresponding to the polyyne structure with alternating bond lengths. Conversely, when the chain is unstrained, the ohmic behaviour of metallic cumulene with uniform bond lengths is observed. This confirms the recent prediction of a metal-insulator transition that is induced by strain. The key role of the contacting leads explains the rectifying behaviour measured in monoatomic carbon chains in a nonsymmetric contact configuration.
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Affiliation(s)
- A La Torre
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS, Université de Strasbourg, 23 rue du Loess, 67034 Strasbourg, France
| | - A Botello-Mendez
- Institute of Condensed Matter and Nanosciences, Université catholique de Louvain, Chemin des étoiles 8, 1348 Louvain-la-Neuve, Belgium
| | - W Baaziz
- Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé, UMR 7515 CNRS Université de Strasbourg, 25 rue Becquerel, 67087 Strasbourg, France
| | - J-C Charlier
- Institute of Condensed Matter and Nanosciences, Université catholique de Louvain, Chemin des étoiles 8, 1348 Louvain-la-Neuve, Belgium
| | - F Banhart
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS, Université de Strasbourg, 23 rue du Loess, 67034 Strasbourg, France
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37
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Banhart F. Chains of carbon atoms: A vision or a new nanomaterial? BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:559-69. [PMID: 25821697 PMCID: PMC4362053 DOI: 10.3762/bjnano.6.58] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 02/02/2015] [Indexed: 05/24/2023]
Abstract
Linear strings of sp(1)-hybridized carbon atoms are considered as a possible phase of carbon since decades. Whereas the debate about the stability of the corresponding bulk phase carbyne continues until today, the existence of isolated chains of carbon atoms has meanwhile been corroborated experimentally. Since graphene, as the two-dimensional sp(2)-bonded allotrope of carbon, has become a vast field, the question about the importance of one-dimensional carbon became of renewed interest. The present article gives an overview of the work that has been carried out on chains of carbon atoms in the past one or two decades. The review concentrates on isolated chains of carbon atoms and summarizes the experimental observations to date. While the experimental information is still very limited, many calculations of the physical and chemical properties have been published in the past years. Some of the most important theoretical studies and their importance in the present experimental situation are reviewed.
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Affiliation(s)
- Florian Banhart
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS, University of Strasbourg, 23 rue du Loess, 67034 Strasbourg, France
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38
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Bachmatiuk A, Zhao J, Gorantla SM, Martinez IGG, Wiedermann J, Lee C, Eckert J, Rummeli MH. Low voltage transmission electron microscopy of graphene. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:515-42. [PMID: 25408379 DOI: 10.1002/smll.201401804] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/27/2014] [Indexed: 05/27/2023]
Abstract
The initial isolation of graphene in 2004 spawned massive interest in this two-dimensional pure sp(2) carbon structure due to its incredible electrical, optical, mechanical, and thermal effects. This in turn led to the rapid development of various characterization tools for graphene. Examples include Raman spectroscopy and scanning tunneling microscopy. However, the one tool with the greatest prowess for characterizing and studying graphene is the transmission electron microscope. State-of-the-art (scanning) transmission electron microscopes enable one to image graphene with atomic resolution, and also to conduct various other characterizations simultaneously. The advent of aberration correctors was timely in that it allowed transmission electron microscopes to operate with reduced acceleration voltages, so that damage to graphene is avoided while still providing atomic resolution. In this comprehensive review, a brief introduction is provided to the technical aspects of transmission electron microscopes relevant to graphene. The reader is then introduced to different specimen preparation techniques for graphene. The different characterization approaches in both transmission electron microscopy and scanning transmission electron microscopy are then discussed, along with the different aspects of electron diffraction and electron energy loss spectroscopy. The use of graphene for other electron microscopy approaches such as in-situ investigations is also presented.
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Affiliation(s)
- Alicja Bachmatiuk
- IBS Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS), Daejon, 305-701, Republic of Korea; IFW Dresden, Institute of Complex Materials, P.O. Box 270116, D-01171, Dresden, Germany; Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, Zabrze, 41-819, Poland
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39
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Gong C, He K, Robertson AW, Yoon E, Lee GD, Warner JH. Spatially dependent lattice deformations for dislocations at the edges of graphene. ACS NANO 2015; 9:656-662. [PMID: 25496495 DOI: 10.1021/nn505996c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We show that dislocations located at the edge of graphene cause different lattice deformations to those located in the bulk lattice. When a dislocation is located near an edge, a decrease in the rippling and increase of the in-plane rotation occurs relative to the dislocations in the bulk. The increased in-plane rotation near the edge causes bond rotations at the edge of graphene to reduce the overall strain in the system. Dislocations were highly stable and remained fixed in their position even when located within a few lattice spacings from the edge of graphene. We study this behavior at the atomic level using aberration-corrected transmission electron microscopy. These results show detailed information about the behavior of dislocations in 2D materials and the strain properties that result.
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Affiliation(s)
- Chuncheng Gong
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
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40
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Zhang X, Yu S, Chen H, Zheng W. TM atoms on B/N doped defective graphene as a catalyst for oxygen reduction reaction: a theoretical study. RSC Adv 2015. [DOI: 10.1039/c5ra15315h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
N-doping can effectively improve the binding strength of metal atoms with divacancies and some TM–VN2 serve as promising ORR catalysts.
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Affiliation(s)
- Xiaoming Zhang
- Department of Materials Science
- Key Laboratory of Mobile Materials
- MOE
- State Key Laboratory of Superhard Materials
- Jilin University
| | - Shansheng Yu
- Department of Materials Science
- Key Laboratory of Mobile Materials
- MOE
- State Key Laboratory of Superhard Materials
- Jilin University
| | - Hong Chen
- Department of Control Science & Engineering
- Jilin University
- Changchun 130012
- PR China
| | - Weitao Zheng
- Department of Materials Science
- Key Laboratory of Mobile Materials
- MOE
- State Key Laboratory of Superhard Materials
- Jilin University
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41
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Kumar GS, Thupakula U, Sarkar PK, Acharya S. Easy extraction of water-soluble graphene quantum dots for light emitting diodes. RSC Adv 2015. [DOI: 10.1039/c5ra01399b] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Graphene quantum dots in powder form obtained in single-step leads fabricating color tunable light emitting diodes with low turn-on voltages.
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Affiliation(s)
- Gundam Sandeep Kumar
- Centre for Advanced Materials
- Indian Association for the Cultivation of Science
- Kolkata-700032
- India
| | - Umamahesh Thupakula
- Centre for Advanced Materials
- Indian Association for the Cultivation of Science
- Kolkata-700032
- India
| | - Piyush Kanti Sarkar
- Centre for Advanced Materials
- Indian Association for the Cultivation of Science
- Kolkata-700032
- India
| | - Somobrata Acharya
- Centre for Advanced Materials
- Indian Association for the Cultivation of Science
- Kolkata-700032
- India
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42
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Skowron ST, Lebedeva IV, Popov AM, Bichoutskaia E. Energetics of atomic scale structure changes in graphene. Chem Soc Rev 2015; 44:3143-76. [DOI: 10.1039/c4cs00499j] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
An overview of theoretical and experimental studies concerned with energetics of atomic scale structure changes in graphene, including thermally activated and electron irradiation-induced processes.
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Affiliation(s)
| | - Irina V. Lebedeva
- Nano-Bio Spectroscopy Group and ETSF Scientific Development Centre
- Departamento de Física de Materiales
- Universidad del Pais Vasco UPV/EHU
- San Sebastian E-20018
- Spain
| | - Andrey M. Popov
- Institute for Spectroscopy of Russian Academy of Sciences
- Moscow 142190
- Russia
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43
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Cretu O, Komsa HP, Lehtinen O, Algara-Siller G, Kaiser U, Suenaga K, Krasheninnikov AV. Experimental observation of boron nitride chains. ACS NANO 2014; 8:11950-7. [PMID: 25299068 DOI: 10.1021/nn5046147] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We report the formation and characterization of boron nitride atomic chains. The chains were made from hexagonal boron nitride sheets using the electron beam inside a transmission electron microscope. We find that the stability and lifetime of the chains are significantly improved when they are supported by another boron nitride layer. With the help of first-principles calculations, we prove the heteroatomic structure of the chains and determine their mechanical and electronic properties. Our study completes the analogy between various boron nitride and carbon polymorphs, in accordance with earlier theoretical predictions.
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Affiliation(s)
- Ovidiu Cretu
- Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
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44
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Ma T, Ren W, Liu Z, Huang L, Ma LP, Ma X, Zhang Z, Peng LM, Cheng HM. Repeated growth-etching-regrowth for large-area defect-free single-crystal graphene by chemical vapor deposition. ACS NANO 2014; 8:12806-12813. [PMID: 25418823 DOI: 10.1021/nn506041t] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Reducing nucleation density and healing structural defects are two challenges for fabricating large-area high-quality single-crystal graphene, which is essential for its electronic and optoelectronic applications. We have developed a method involving chemical vapor deposition (CVD) growth followed by repeated etching-regrowth, to solve both problems at once. Using this method, we can obtain single-crystal graphene domains with a size much larger than that allowed by the nucleation density in the initial growth and efficiently heal structural defects similar to graphitization but at a much lower temperature, both of which are impossible to realize by conventional CVD. Using this method with Pt as a growth substrate, we have grown ∼3 mm defect-free single-crystal graphene domains with a carrier mobility up to 13,000 cm2 V(-1) s(-1) under ambient conditions.
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Affiliation(s)
- Teng Ma
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences , 72 Wenhua Road, Shenyang 110016, People's Republic of China
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45
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Saraiva-Souza A, Smeu M, Zhang L, Souza Filho AG, Guo H, Ratner MA. Molecular Spintronics: Destructive Quantum Interference Controlled by a Gate. J Am Chem Soc 2014; 136:15065-71. [DOI: 10.1021/ja508537n] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Aldilene Saraiva-Souza
- Centre
for the Physics of Materials and Department of Physics, McGill University, Montreal, QC H3A 2T8, Canada
| | - Manuel Smeu
- Departamento
of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Lei Zhang
- Centre
for the Physics of Materials and Department of Physics, McGill University, Montreal, QC H3A 2T8, Canada
| | | | - Hong Guo
- Centre
for the Physics of Materials and Department of Physics, McGill University, Montreal, QC H3A 2T8, Canada
| | - Mark A. Ratner
- Departamento
of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
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46
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Zhang Z, Luo L, Chen G, Ding Y, Deng D, Fan C. Tryptamine functionalized reduced graphene oxide for label-free DNA impedimetric biosensing. Biosens Bioelectron 2014; 60:161-6. [DOI: 10.1016/j.bios.2014.03.067] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 03/13/2014] [Accepted: 03/31/2014] [Indexed: 11/30/2022]
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47
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Yazyev OV, Chen YP. Polycrystalline graphene and other two-dimensional materials. NATURE NANOTECHNOLOGY 2014; 9:755-67. [PMID: 25152238 DOI: 10.1038/nnano.2014.166] [Citation(s) in RCA: 204] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 07/15/2014] [Indexed: 05/02/2023]
Abstract
Graphene, a single atomic layer of graphitic carbon, has attracted intense attention because of its extraordinary properties that make it a suitable material for a wide range of technological applications. Large-area graphene films, which are necessary for industrial applications, are typically polycrystalline - that is, composed of single-crystalline grains of varying orientation joined by grain boundaries. Here, we present a review of the large body of research reported in the past few years on polycrystalline graphene. We discuss its growth and formation, the microscopic structure of grain boundaries and their relations to other types of topological defect such as dislocations. The Review further covers electronic transport, optical and mechanical properties pertaining to the characterizations of grain boundaries, and applications of polycrystalline graphene. We also discuss research, still in its infancy, performed on other two-dimensional materials such as transition metal dichalcogenides, and offer perspectives for future directions of research.
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Affiliation(s)
- Oleg V Yazyev
- Institute of Theoretical Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Yong P Chen
- Department of Physics and School of Electrical and Computer Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
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48
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Kashtiban RJ, Dyson MA, Nair RR, Zan R, Wong SL, Ramasse Q, Geim AK, Bangert U, Sloan J. Atomically resolved imaging of highly ordered alternating fluorinated graphene. Nat Commun 2014; 5:4902. [DOI: 10.1038/ncomms5902] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 08/01/2014] [Indexed: 11/09/2022] Open
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49
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Lehtinen O, Tsai IL, Jalil R, Nair RR, Keinonen J, Kaiser U, Grigorieva IV. Non-invasive transmission electron microscopy of vacancy defects in graphene produced by ion irradiation. NANOSCALE 2014; 6:6569-6576. [PMID: 24802077 DOI: 10.1039/c4nr01918k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Irradiation with high-energy ions has been widely suggested as a tool to engineer properties of graphene. Experiments show that it indeed has a strong effect on graphene's transport, magnetic and mechanical characteristics. However, to use ion irradiation as an engineering tool requires understanding of the type and detailed characteristics of the produced defects which is still lacking, as the use of high-resolution transmission microscopy (HRTEM)--the only technique allowing direct imaging of atomic-scale defects--often modifies or even creates defects during imaging, thus making it impossible to determine the intrinsic atomic structure. Here we show that encapsulating the studied graphene sample between two other (protective) graphene sheets allows non-invasive HRTEM imaging and reliable identification of atomic-scale defects. Using this simple technique, we demonstrate that proton irradiation of graphene produces reconstructed monovacancies, which explains the profound effect that such defects have on graphene's magnetic and transport properties. This finding resolves the existing uncertainty with regard to the effect of ion irradiation on the electronic structure of graphene.
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Affiliation(s)
- Ossi Lehtinen
- Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, University of Ulm, 89081 Ulm, Germany.
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Robertson AW, Lee GD, He K, Yoon E, Kirkland AI, Warner JH. Stability and dynamics of the tetravacancy in graphene. NANO LETTERS 2014; 14:1634-1642. [PMID: 24588782 DOI: 10.1021/nl500119p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The relative prevalence of various configurations of the tetravacancy defect in monolayer graphene has been examined using aberration corrected transmission electron microscopy (TEM). It was found that the two most common structures are extended linear defect structures, with the 3-fold symmetric Y-tetravacancy seldom imaged, in spite of this being a low energy state. Using density functional theory and tight-binding molecular dynamics calculations, we have determined that our TEM observations support a dynamic model of the tetravacancy under electron irradiation, with Stone-Wales bond rotations providing a mechanism for defect relaxation into lowest energy configurations. The most prevalent tetravacancy structures, while not necessarily having the lowest formation energy, are found to have a local energy minimum in the overall energy landscape for tetravacancies, explaining their relatively high occurrence.
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Affiliation(s)
- Alex W Robertson
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
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