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Mishra S, Liu F, Shakthivel D, Rai B, Georgiev V. Molecular dynamics simulation-based study to analyse the properties of entrapped water between gold and graphene 2D interfaces. NANOSCALE ADVANCES 2024; 6:2371-2379. [PMID: 38694470 PMCID: PMC11059550 DOI: 10.1039/d3na00878a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 03/17/2024] [Indexed: 05/04/2024]
Abstract
Heterostructures based on graphene and other 2D materials have received significant attention in recent years. However, it is challenging to fabricate them with an ultra-clean interface due to unwanted foreign molecules, which usually get introduced during their transfer to a desired substrate. Clean nanofabrication is critical for the utilization of these materials in 2D nanoelectronics devices and circuits, and therefore, it is important to understand the influence of the "non-ideal" interface. Inspired by the wet-transfer process of the CVD-grown graphene, herein, we present an atomistic simulation of the graphene-Au interface, where water molecules often get trapped during the transfer process. By using molecular dynamics (MD) simulations, we investigated the structural variations of the trapped water and the traction-separation curve derived from the graphene-Au interface at 300 K. We observed the formation of an ice-like structure with square-ice patterns when the thickness of the water film was <5 Å. This could cause undesirable strain in the graphene layer and hence affect the performance of devices developed from it. We also observed that at higher thicknesses the water film is predominantly present in the liquid state. The traction separation curve showed that the adhesion of graphene is better in the presence of an ice-like structure. This study explains the behaviour of water confined at the nanoscale region and advances our understanding of the graphene-Au interface in 2D nanoelectronics devices and circuits.
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Affiliation(s)
- Shashank Mishra
- James Watt School of Engineering, University of Glasgow G12 8QQ Glasgow UK
| | - Fengyuan Liu
- James Watt School of Engineering, University of Glasgow G12 8QQ Glasgow UK
| | | | - Beena Rai
- TCS Research, Tata Consultancy Services Limited Pune 411013 India
| | - Vihar Georgiev
- James Watt School of Engineering, University of Glasgow G12 8QQ Glasgow UK
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2
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Non-covalent interactions of graphene surface: Mechanisms and applications. Chem 2022. [DOI: 10.1016/j.chempr.2021.12.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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3
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Deng A, Hu C, Shen P, Chen J, Luo X, Lyu B, Watanabe K, Taniguchi T, Wang R, Liang Q, Ma J, Shi Z. Non-Local Electrostatic Gating Effect in Graphene Revealed by Infrared Nano-Imaging. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2105687. [PMID: 34837309 DOI: 10.1002/smll.202105687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/17/2021] [Indexed: 06/13/2023]
Abstract
Electrostatic gating lies in the heart of field effect transistor (FET) devices and modern integrated circuits. To achieve efficient gate tunability, the gate electrode has to be placed very close to the conduction channel, typically a few nanometers. Remote control of a FET device through a gate electrode located far away is highly desirable, because it not only reduces the complexity of device fabrication, but also enables the design of novel devices with new functionalities. Here, a non-local electrostatic gating effect in graphene devices using scanning near-field optical microscopy (SNOM)-a technique that can probe local charge density in graphene-is reported. Remarkably, the charge density of the graphene region tens of micrometers away from a local gate can be efficiently tuned. The observed non-local gating effect is initially driven by an in-plane electric field induced by the quantum capacitance of graphene, and further largely enhanced by adsorbed polarized water molecules. This study reveals a non-local phenomenon of Dirac electrons, provides a deep understanding of in-plane screening from Dirac electrons, and paves the way for designing novel electronic devices with remote gate control.
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Affiliation(s)
- Aolin Deng
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Cheng Hu
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Peiyue Shen
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Jiajun Chen
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Xingdong Luo
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Bosai Lyu
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Rongming Wang
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Qi Liang
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Jie Ma
- Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, China
| | - Zhiwen Shi
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
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4
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Bampoulis P. Temperature induced dynamics of water confined between graphene and MoS 2. J Chem Phys 2021; 154:134705. [PMID: 33832247 DOI: 10.1063/5.0044123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Water trapped between MoS2 and graphene assumes a form of ice composed of two planar hexagonal layers with a non-tetrahedral geometry. Additional water does not wet these ice layers but forms three-dimensional droplets. Here, we have investigated the temperature induced dewetting dynamics of the confined ice and water droplets. The ice crystals gradually decrease in size with increasing substrate temperature and completely vanish at about 80 °C. Further heating to 100 °C induces changes in water droplet density, size, and shape through droplet coalescence and dissolution. However, even prolonged annealing at 100 °C does not completely dry the interface. The dewetting dynamics are controlled by the graphene cover. Thicker graphene flakes allow faster water diffusion as a consequence of the reduction of graphene's conformity along the ice crystal's edges, which leaves enough space for water molecules to diffuse along the ice edges and evaporate to the environment through defects in the graphene cover.
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Affiliation(s)
- P Bampoulis
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands and II. Physikalisches Institut, Universität zu Köln, Cologne D-50937, Germany
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5
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Rai S, Sharma N, Rai D. Structured water chains in external electric fields. Mol Phys 2020. [DOI: 10.1080/00268976.2019.1662957] [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]
Affiliation(s)
- Smita Rai
- Department of Physics, Sikkim University, Samdur, India
| | - Nayan Sharma
- Department of Physics, Sikkim University, Samdur, India
| | - Dhurba Rai
- Department of Physics, Sikkim University, Samdur, India
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6
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Hong Y, Wang S, Li Q, Song X, Wang Z, Zhang X, Besenbacher F, Dong M. Interfacial icelike water local doping of graphene. NANOSCALE 2019; 11:19334-19340. [PMID: 31423505 DOI: 10.1039/c9nr05832j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Charge transfer at interfaces plays a critical role in the performance of graphene based electronic devices. However, separate control of the charge transfer process in the graphene/SiO2 system is still challenging. Herein, we investigate the effects of the trapped interfacial icelike water layer on the charge transfer between graphene and the SiO2/Si substrate through recording the surface potential changes induced by partial removal of the interfacial icelike water layer upon in situ heating. The scanning Kelvin probe microscopy surface potential mapping shows that the graphene is electronically modified by the icelike water layer as the electron density transfers from graphene to the icelike water layer, resulting in hole-doping of graphene, which was also confirmed by the graphene field effect transistor electrical transport measurements. In addition, the density functional calculations provide in-depth insight into the electronic contributions of the icelike water layer to graphene and the charge transfer mechanism. This research will improve our ability to manipulate graphene's electronic properties for diverse applications, such as humidity sensing.
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Affiliation(s)
- Yue Hong
- Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, and School of Chemistry and Chemical Engineering, Shandong University, Shandong, Jinan 250100, China.
| | - Sanmei Wang
- Institute of Nanosurface Science and Engineering, Shenzhen University, Guangdong, Shenzhen 518060, China.
| | - Qiang Li
- Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, and School of Chemistry and Chemical Engineering, Shandong University, Shandong, Jinan 250100, China. and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, DK-8000, Denmark.
| | - Xin Song
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, DK-8000, Denmark.
| | - Zegao Wang
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, DK-8000, Denmark.
| | - Xi Zhang
- Institute of Nanosurface Science and Engineering, Shenzhen University, Guangdong, Shenzhen 518060, China.
| | - Flemming Besenbacher
- Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, and School of Chemistry and Chemical Engineering, Shandong University, Shandong, Jinan 250100, China. and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, DK-8000, Denmark.
| | - Mingdong Dong
- Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, and School of Chemistry and Chemical Engineering, Shandong University, Shandong, Jinan 250100, China. and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, DK-8000, Denmark.
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7
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Si N, Shen T, Zhou D, Tang Q, Jiang Y, Ji Q, Huang H, Liu W, Li S, Niu T. Imaging and Dynamics of Water Hexamer Confined in Nanopores. ACS NANO 2019; 13:10622-10630. [PMID: 31487147 DOI: 10.1021/acsnano.9b04835] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Epitaxial two-dimensional (2D) nanostructures with regular patterns show great promise as templates for adsorbate confinement. Prospectively, employing 2D semiconductors with reduced density of states leads to a long excited-state lifetime that allows us to directly image the dynamics of the adsorbate. We show that epitaxial blue phosphorene (blueP) on Au(111) provides such a platform to trap water molecules in the periodic nanopores without formation of strong bonds. The trapped water aggregate is tentatively assigned to a hexamer based on our scanning tunneling microscopy studies and first-principles calculations. Real-space observation of conformational switching of the hexamer induced by inelastic electrons is achieved by using low-temperature scanning tunneling microscopy with molecular resolution. We found a localized interfacial charge rearrangement between the water hexamer and P atoms underneath that is responsible for the reversible desorption and adsorption of water molecules by changing the sample bias polarity from positive to negative, offering a promising strategy for engineering the electronic properties of blueP.
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Affiliation(s)
- Nan Si
- Herbert Gleiter Institute of Nanoscience, School of Material Science and Engineering , Nanjing University of Science & Technology , No. 200 , Xiaolingwei, Nanjing 210094 , People's Republic of China
| | - Tao Shen
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China
| | - Dechun Zhou
- Herbert Gleiter Institute of Nanoscience, School of Material Science and Engineering , Nanjing University of Science & Technology , No. 200 , Xiaolingwei, Nanjing 210094 , People's Republic of China
| | - Qin Tang
- Herbert Gleiter Institute of Nanoscience, School of Material Science and Engineering , Nanjing University of Science & Technology , No. 200 , Xiaolingwei, Nanjing 210094 , People's Republic of China
| | - Yixuan Jiang
- Herbert Gleiter Institute of Nanoscience, School of Material Science and Engineering , Nanjing University of Science & Technology , No. 200 , Xiaolingwei, Nanjing 210094 , People's Republic of China
| | - Qingmin Ji
- Herbert Gleiter Institute of Nanoscience, School of Material Science and Engineering , Nanjing University of Science & Technology , No. 200 , Xiaolingwei, Nanjing 210094 , People's Republic of China
| | - Han Huang
- Hunan Key Laboratory of Super-microstructure and Ultrafast Process, College of Physics and Electronics , Central South University , Changsha 410083 , People's Republic of China
| | - Wei Liu
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China
| | - Shuang Li
- Nano and Heterogeneous Materials Center, School of Materials Science and Engineering , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China
| | - Tianchao Niu
- Herbert Gleiter Institute of Nanoscience, School of Material Science and Engineering , Nanjing University of Science & Technology , No. 200 , Xiaolingwei, Nanjing 210094 , People's Republic of China
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8
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Li Z, Li S, Chen HYT, Gao N, Schouteden K, Qiang X, Zhao J, Brems S, Huyghebaert C, Van Haesendonck C. Strongly Hole-Doped and Highly Decoupled Graphene on Platinum by Water Intercalation. J Phys Chem Lett 2019; 10:3998-4002. [PMID: 31260314 DOI: 10.1021/acs.jpclett.9b01488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Scanning tunneling microscopy and spectroscopy experiments under ultrahigh vacuum and low-temperature conditions have been performed on water-intercalated graphene on Pt(111). We find that the confined water layer, with a thickness around 0.35 nm, induces a strong hole doping in graphene, i.e., the Dirac point locates at round 0.64 eV above the Fermi level. This can be explained by the presence of a single "puckered bilayer" of ice-Ih, which has not been experimentally found on bare Pt(111), being confined in between graphene and Pt(111) surface. Moreover, the water intercalation makes graphene highly decoupled from the substrate, allowing us to reveal the intrinsic graphene phonons and double Rydberg series of even and odd symmetry image-potential states. Our work not only demonstrates that the electronic properties of graphene can be tuned by the confined water layer between graphene and the substrate, but also provides a generally applicable method to study the intrinsic properties of graphene as well as of other supported two-dimensional materials.
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Affiliation(s)
- Zhe Li
- State Key Laboratory on Tunable Laser Technology, Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, School of Science , Harbin Institute of Technology (Shenzhen) , Shenzhen 518055 , China
| | - Shiqi Li
- Key Laboratory of Materials Modification by Laser , Ion and Electron Beams(Dalian University of Technology) , Ministry of Education, Dalian 116024 , China
| | - Hsin-Yi Tiffany Chen
- Department of Engineering and System Science , National Tsing Hua University , Hsinchu 30010 , Taiwan
| | - Nan Gao
- Key Laboratory of Materials Modification by Laser , Ion and Electron Beams(Dalian University of Technology) , Ministry of Education, Dalian 116024 , China
| | - Koen Schouteden
- Laboratory of Solid-State Physics and Magnetism , KU Leuven , BE-3001 Leuven , Belgium
| | - Xiaoming Qiang
- Key Laboratory of Materials Modification by Laser , Ion and Electron Beams(Dalian University of Technology) , Ministry of Education, Dalian 116024 , China
| | - Jijun Zhao
- Key Laboratory of Materials Modification by Laser , Ion and Electron Beams(Dalian University of Technology) , Ministry of Education, Dalian 116024 , China
| | - Steven Brems
- Interuniversitair Micro-Electronica Centrum (imec) vzw , Kapeldreef 75 , BE-3001 Leuven , Belgium
| | - Cedric Huyghebaert
- Interuniversitair Micro-Electronica Centrum (imec) vzw , Kapeldreef 75 , BE-3001 Leuven , Belgium
| | - Chris Van Haesendonck
- Laboratory of Solid-State Physics and Magnetism , KU Leuven , BE-3001 Leuven , Belgium
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9
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Wang G, Zhang M, Chen D, Guo Q, Feng X, Niu T, Liu X, Li A, Lai J, Sun D, Liao Z, Wang Y, Chu PK, Ding G, Xie X, Di Z, Wang X. Seamless lateral graphene p-n junctions formed by selective in situ doping for high-performance photodetectors. Nat Commun 2018; 9:5168. [PMID: 30518867 PMCID: PMC6281711 DOI: 10.1038/s41467-018-07555-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 10/29/2018] [Indexed: 11/09/2022] Open
Abstract
Lateral graphene p–n junctions are important since they constitute the core components in a variety of electronic/photonic systems. However, formation of lateral graphene p–n junctions with a controllable doping levels is still a great challenge due to the monolayer feature of graphene. Herein, by performing selective ion implantation and in situ growth by dynamic chemical vapor deposition, direct formation of seamless lateral graphene p–n junctions with spatial control and tunable doping is demonstrated. Uniform lattice substitution with heteroatoms is achieved in both the boron-doped and nitrogen-doped regions and photoelectrical assessment reveals that the seamless lateral p–n junctions exhibit a distinct photocurrent response under ambient conditions. As ion implantation is a standard technique in microelectronics, our study suggests a simple and effective strategy for mass production of graphene p–n junctions with batch capability and spatial controllability, which can be readily integrated into the production of graphene-based electronics and photonics. Fabricating lateral graphene p–n junctions with controlled doping levels is instrumental to realize ultrafast and efficient optoelectronic devices. Here, the authors report a seamless graphene based photodetector doped by selective ion implantation and in-situ chemical vapour deposition.
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Affiliation(s)
- Gang Wang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China.,Department of Microelectronic Science and Engineering, Faculty of Science, Ningbo University, Ningbo, 315211, P.R. China
| | - Miao Zhang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Da Chen
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China.,Department of Microelectronic Science and Engineering, Faculty of Science, Ningbo University, Ningbo, 315211, P.R. China
| | - Qinglei Guo
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Xuefei Feng
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Tianchao Niu
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Xiaosong Liu
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Ang Li
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Jiawei Lai
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, P.R. China
| | - Dong Sun
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, P.R. China
| | - Zhimin Liao
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, P.R. China
| | - Yongqiang Wang
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Paul K Chu
- Department of Physics and Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P.R. China
| | - Guqiao Ding
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Xiaoming Xie
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
| | - Zengfeng Di
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China.
| | - Xi Wang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, P.R. China
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10
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Sun J, Finklea HO, Liu Y. Characterization and electrolytic cleaning of poly(methyl methacrylate) residues on transferred chemical vapor deposited graphene. NANOTECHNOLOGY 2017; 28:125703. [PMID: 28163262 DOI: 10.1088/1361-6528/aa5e55] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Poly(methyl methacrylate) (PMMA) residue has long been a critical challenge for practical applications of the transferred chemical vapor deposited (CVD) graphene. Thermal annealing is empirically used for the removal of the PMMA residue; however experiments imply that there are still small amounts of residues left after thermal annealing which are hard to remove with conventional methods. In this paper, the thermal degradation of the PMMA residue upon annealing was studied by Raman spectroscopy. The study reveals that post-annealing residues are generated by the elimination of methoxycarbonyl side chains in PMMA and are believed to be absorbed on graphene via the π-π interaction between the conjugated unsaturated carbon segments and graphene. The post-annealing residues are difficult to remove by further annealing in a non-oxidative atmosphere due to their thermal and chemical stability. An electrolytic cleaning method was shown to be effective in removing these post-annealing residues while preserving the underlying graphene lattice based on Raman spectroscopy and atomic force microscopy studies. Additionally, a solution-gated field effect transistor was used to study the transport properties of the transferred CVD graphene before thermal annealing, after thermal annealing, and after electrolytic cleaning, respectively. The results show that the carrier mobility was significantly improved, and that the p-doping was reduced by removing PMMA residues and post-annealing residues. These studies provide a more in-depth understanding on the thermal annealing process for the removal of the PMMA residues from transferred CVD graphene and a new approach to remove the post-annealing residues, resulting in a residue-free graphene.
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Affiliation(s)
- Jianbo Sun
- Lane Department of Computer Science and Electrical Engineering, West Virginia University, Morgantown, WV 26506, United States of America
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11
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Bampoulis P, Witteveen JP, Kooij ES, Lohse D, Poelsema B, Zandvliet HJW. Structure and Dynamics of Confined Alcohol-Water Mixtures. ACS NANO 2016; 10:6762-8. [PMID: 27337245 DOI: 10.1021/acsnano.6b02333] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The effect of confinement between mica and graphene on the structure and dynamics of alcohol-water mixtures has been studied in situ and in real time at the molecular level by atomic force microscopy (AFM) at room temperature. AFM images reveal that the adsorbed molecules are segregated into faceted alcohol-rich islands on top of an ice layer on mica, surrounded by a pre-existing multilayer water-rich film. These faceted islands are in direct contact with the graphene surface, revealing a preferred adsorption site. Moreover, alcohol adsorption at low relative humidity (RH) reveals a strong preference of the alcohol molecules for the ordered ice interface. The growth dynamics of the alcohol islands is governed by supersaturation, temperature, the free energy of attachment of molecules to the island edge and two-dimensional (2D) diffusion. The measured diffusion coefficients display a size dependence on the molecular size of the alcohols, and are about 6 orders of magnitude smaller than the bulk diffusion coefficients, demonstrating the effect of confinement on the behavior of the alcohols. These experimental results provide new insights into the behavior of multicomponent fluids in confined geometries, which is of paramount importance in nanofluidics and biology.
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Affiliation(s)
- Pantelis Bampoulis
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
- Physics of Fluids and J.M. Burgers Centre for Fluid Mechanics, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
| | - Jorn P Witteveen
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
| | - E Stefan Kooij
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
| | - Detlef Lohse
- Physics of Fluids and J.M. Burgers Centre for Fluid Mechanics, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
- Max Planck Institute for Dynamics and Self-Organization , Am Fassberg, 37077 Göttingen, Germany
| | - Bene Poelsema
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
| | - Harold J W Zandvliet
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500AE Enschede, The Netherlands
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12
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Yasuda S, Kumagai R, Nakashima K, Murakoshi K. Electrochemical Potential Stabilization of Reconstructed Au(111) Structure by Monolayer Coverage with Graphene. J Phys Chem Lett 2015; 6:3403-3409. [PMID: 26279244 DOI: 10.1021/acs.jpclett.5b01488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The electrochemical properties of a monolayer graphene grown on a Au(111) electrode were studied using cyclic voltammetry (CV) and electrochemical scanning tunneling microscopy (EC-STM). CV and EC-STM measurements in 0.1 M H2SO4 aqueous solution revealed that graphene grown on the reconstructed (22 × √3) Au(111) structure effectively inhibited potential-induced structural transitions between reconstructed (22 × √3) and unreconstructed (1 × 1), and the adsorption/desorption of SO4(2-) ions, which are intrinsic behavior of the bare Au(111) surface. The underlying reconstructed structure was significantly stabilized by covering with monolayer graphene over a wide potential range between -0.2 V and +1.35 V vs Ag/AgCl (saturated KCl), which is much wider than that for bare Au(111) (-0.2 to + 0.35 V vs Ag/AgCl (saturated KCl)). Such high stability has not been reported to date; therefore, these results are considered to be important for understanding the fundamentals of surface reconstruction and also serve to open a new branch of electrochemistry related to graphene/metal-electrolyte interfaces.
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Affiliation(s)
- Satoshi Yasuda
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo, Hokkaido 060-0810, Japan
- Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama 332-0012, Japan
| | - Ryota Kumagai
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo, Hokkaido 060-0810, Japan
| | - Koji Nakashima
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo, Hokkaido 060-0810, Japan
| | - Kei Murakoshi
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo, Hokkaido 060-0810, Japan
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Graphene-enabled electron microscopy and correlated super-resolution microscopy of wet cells. Nat Commun 2015; 6:7384. [PMID: 26066680 PMCID: PMC4490578 DOI: 10.1038/ncomms8384] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 04/30/2015] [Indexed: 12/23/2022] Open
Abstract
The application of electron microscopy to hydrated biological samples has been limited by high-vacuum operating conditions. Traditional methods utilize harsh and laborious sample dehydration procedures, often leading to structural artefacts and creating difficulties for correlating results with high-resolution fluorescence microscopy. Here, we utilize graphene, a single-atom-thick carbon meshwork, as the thinnest possible impermeable and conductive membrane to protect animal cells from vacuum, thus enabling high-resolution electron microscopy of wet and untreated whole cells with exceptional ease. Our approach further allows for facile correlative super-resolution and electron microscopy of wet cells directly on the culturing substrate. In particular, individual cytoskeletal actin filaments are resolved in hydrated samples through electron microscopy and well correlated with super-resolution results. Preparing biological material for electron microscopy (EM) involves harsh processing steps that can poorly preserve cellular ultrastructure. Here the authors apply a single layer of graphene onto wet cells to enable direct EM using low voltage, and correlate actin filaments and mitochondria using super-resolution microscopy.
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Varghese JO, Agbo P, Sutherland AM, Brar VW, Rossman GR, Gray HB, Heath JR. The influence of water on the optical properties of single-layer molybdenum disulfide. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:2734-2740. [PMID: 25787228 DOI: 10.1002/adma.201500555] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 02/26/2015] [Indexed: 06/04/2023]
Abstract
Adsorbed molecules can significantly affect the properties of atomically thin materials. Physisorbed water plays a significant role in altering the optoelectronic properties of single-layer MoS2 , one such 2D film. Here the distinct quenching effect of adsorbed water on the photoluminescence of single-layer MoS2 is demonstrated through scanning-probe and optical microscopy.
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Affiliation(s)
- Joseph O Varghese
- Division of Chemistry and Chemical Engineering, California Institute of Technology, MC 127-72, Pasadena, CA, 91125, USA
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15
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Abstract
CONSPECTUS: The interface between water and other materials under ambient conditions is of fundamental importance due to its relevance in daily life and a broad range of scientific research. The structural and dynamic properties of water at an interface have been proven to be significantly difference than those of bulk water. However, the exact nature of these interfacial water adlayers at ambient conditions is still under debate. Recent scanning probe microscopy (SPM) experiments, where two-dimensional (2D) materials as ultrathin coatings are utilized to assist the visualization of interfacial water adlayers, have made remarkable progress on interfacial water and started to clarify some of these fundamental scientific questions. In this Account, we review the recently conducted research exploring the properties of confined water between 2D materials and various surfaces under ambient conditions. Initially, we review the earlier studies of water adsorbed on hydrophilic substrates under ambient conditions in the absence of 2D coating materials, which shows the direct microscopic results. Subsequently, we focus on the studies of water adlayer growth at both hydrophilic and hydrophobic substrates in the presence of 2D coating materials. Ice-like water adlayers confined between hydrophobic graphene and hydrophilic substrates can be directly observed in detail by SPM. It was found that the packing structure of the water adlayer was determined by the hydrophilic substrates, while the orientation of intercalation water domains was directed by the graphene coating. In contrast to hydrophilic substrates, liquid-like nanodroplets confined between hydrophobic graphene and hydrophobic substrates appear close to step edges and atomic-scale surface defects, indicating that atomic-scale surface defects play significant roles in determining the adsorption of water on hydrophobic substrates. In addition, we also review the phenomena of confined water between 2D hydrophilic MoS2 and the hydrophilic substrate. Finally, we further discuss researchers taking advantage of 2D graphene coatings to stabilize confined water nanodroplets to manipulate nanofluidics through applying an external force by using novel SPM techniques. Moreover, for future technology application purposes, the doping effect of confined water is also discussed. The use of 2D materials as ultrathin coatings to investigate the properties of confined water under ambient conditions is developing and recognized as a profound approach to gain fundamental knowledge of water. This ideal model system will provide new opportunities in various research fields.
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Affiliation(s)
- Qiang Li
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark
| | - Jie Song
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark
| | - Flemming Besenbacher
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark
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Graphene on mica - intercalated water trapped for life. Sci Rep 2014; 4:6003. [PMID: 25132493 PMCID: PMC4135328 DOI: 10.1038/srep06003] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/22/2014] [Indexed: 01/05/2023] Open
Abstract
In this work we study the effect of thermal processing of exfoliated graphene on mica with respect to changes in graphene morphology and surface potential. Mild annealing to temperatures of about 200°C leads to the removal of small amounts of intercalated water at graphene edges. By heating to 600°C the areas without intercalated water are substantially increased enabling a quantification of the charge transfer properties of the water layer by locally resolved Kelvin probe force microscopy data. A complete removal on a global scale cannot be achieved because mica begins to decompose at temperatures above 600°C. By correlating Kelvin probe force microscopy and Raman spectroscopy maps we find a transition from p-type to n-type doping of graphene during thermal processing which is driven by the dehydration of the mica substrate and an accumulation of defects in the graphene sheet.
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Influence of graphene exfoliation on the properties of water-containing adlayers visualized by graphenes and scanning force microscopy. J Colloid Interface Sci 2013; 407:500-4. [DOI: 10.1016/j.jcis.2013.06.034] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 06/11/2013] [Accepted: 06/12/2013] [Indexed: 11/17/2022]
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18
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Paulus GLC, Wang QH, Ulissi ZW, McNicholas TP, Vijayaraghavan A, Shih CJ, Jin Z, Strano MS. Charge transfer at junctions of a single layer of graphene and a metallic single walled carbon nanotube. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:1954-63. [PMID: 23281165 DOI: 10.1002/smll.201201034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 08/27/2012] [Indexed: 05/08/2023]
Abstract
Junctions between a single walled carbon nanotube (SWNT) and a monolayer of graphene are fabricated and studied for the first time. A single layer graphene (SLG) sheet grown by chemical vapor deposition (CVD) is transferred onto a SiO₂/Si wafer with aligned CVD-grown SWNTs. Raman spectroscopy is used to identify metallic-SWNT/SLG junctions, and a method for spectroscopic deconvolution of the overlapping G peaks of the SWNT and the SLG is reported, making use of the polarization dependence of the SWNT. A comparison of the Raman peak positions and intensities of the individual SWNT and graphene to those of the SWNT-graphene junction indicates an electron transfer of 1.12 × 10¹³ cm⁻² from the SWNT to the graphene. This direction of charge transfer is in agreement with the work functions of the SWNT and graphene. The compression of the SWNT by the graphene increases the broadening of the radial breathing mode (RBM) peak from 3.6 ± 0.3 to 4.6 ± 0.5 cm⁻¹ and of the G peak from 13 ± 1 to 18 ± 1 cm⁻¹, in reasonable agreement with molecular dynamics simulations. However, the RBM and G peak position shifts are primarily due to charge transfer with minimal contributions from strain. With this method, the ability to dope graphene with nanometer resolution is demonstrated.
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Affiliation(s)
- Geraldine L C Paulus
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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Tian H, Yang Y, Xie D, Ren TL, Shu Y, Sun H, Zhou CJ, Liu X, Tao LQ, Ge J, Zhang CH, Zhang Y. Laser directed lithography of asymmetric graphene ribbons on a polydimethylsiloxane trench structure. Phys Chem Chem Phys 2013; 15:6825-30. [PMID: 23545537 DOI: 10.1039/c3cp50538c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Recently, manipulating heat transport by asymmetric graphene ribbons has received significant attention, in which phonons in the carbon lattice are used to carry energy. In addition to heat control, asymmetric graphene ribbons might also have broad applications in renewable energy engineering, such as thermoelectric energy harvesting. Here, we transfer a single sheet of graphene over a 5 μm trench of polydimethylsiloxane (PDMS) structure. By using a laser (1.77 mW, 1 μm diameter spot size, 517 nm wavelength) focusing on one side of the suspended graphene, a triangular shaped graphene ribbon is obtained. As the graphene has a negative thermal expansion coefficient, local laser heating could make the affected graphene area shrink and eventually break. Theoretical calculation shows that the 1.77 mW laser could create a local hot spot as high as 1462.5 °C, which could induce an asymmetric shape structure. We also find the temperature coefficient (-13.06 cm(-1) mW) of suspended graphene on PDMS trench substrate is ten times higher than that reported on SiO2/Si trench substrate. Collectively, our results raise the exciting prospect that the realization of graphene with asymmetric shape on thermally insulating substrate is technologically feasible, which may open up important applications in thermal circuits and thermal management.
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Affiliation(s)
- He Tian
- Tsinghua National Laboratory for Information Science and Technology (TNList), Institute of Microelectronics, Tsinghua University, Beijing 100084, China
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Goncher SJ, Zhao L, Pasupathy AN, Flynn GW. Substrate level control of the local doping in graphene. NANO LETTERS 2013; 13:1386-1392. [PMID: 23461627 DOI: 10.1021/nl3039508] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Graphene exfoliated onto muscovite mica is studied using ultrahigh vacuum scanning tunneling microscopy (UHV-STM) techniques. Mica provides an interesting dielectric substrate interface to measure the properties of graphene due to the ultraflat nature of a cleaved mica surface and the surface electric dipoles it possesses. Flat regions of the mica surface show some surface modulation of the graphene topography (24 pm) due to topographic modulation of the mica surface and full conformation of the graphene to that surface. In addition to these ultraflat regions, plateaus of varying size having been found. A comparison of topographic images and STS measurements show that these plateaus are of two types: one with characteristics of water monolayer formation between the graphene and mica, and the other arising from potassium ions trapped at the interfacial region. Immediately above the water induced plateaus, graphene is insulated from charge doping, while p-type doping is observed in areas adjacent to these water nucleation points. However, above and in the neighborhood of interfacial potassium ions, only n-type doping is observed. Graphene regions above the potassium ions are more strongly n-doped than regions adjacent to these alkali atom plateaus. Furthermore, a direct correlation of these Fermi level shifts with topographic features is seen without the random charge carrier density modulation observed in other dielectric substrates. This suggests a possible route to nanoscopic control of the local electron and hole doping in graphene via specific substrate architecture.
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Affiliation(s)
- Scott J Goncher
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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Chen T, Zou Y, Yu C, Zhou X, Li Y. Heteronuclear Cu(II)–Mn(II)–Cu(II) Complex Constructed from Metallo-Ligand Through Carboxylate Oxygens: Coexistence of Water Hexamers. J Inorg Organomet Polym Mater 2012. [DOI: 10.1007/s10904-012-9703-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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D'Urso L, Satriano C, Forte G, Compagnini G, Puglisi O. Water structure and charge transfer phenomena at the liquid–graphene interface. Phys Chem Chem Phys 2012; 14:14605-10. [DOI: 10.1039/c2cp42249b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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