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Verma AK, Singh J, Nguyen-Tri P. Gold-Deposited Graphene Nanosheets for Self-Cleaning Graphene Surface-Enhanced Raman Spectroscopy with Superior Charge-Transfer Contribution. ACS APPLIED MATERIALS & INTERFACES 2024; 16:10969-10983. [PMID: 38355426 DOI: 10.1021/acsami.3c17303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
The interaction of graphene with metals initiates charge-transfer interaction-induced chemical enhancements, which critically depend on the doping effect from deposited metallic configurations. In this paper, we have explored the gold nanoparticle-decorated monolayer graphene nanosheets for the large graphene-induced Raman enhancement of adsorbed analytes, indicating the surface-enhanced Raman spectroscopy (SERS) capabilities of metal-doped graphene (G-SERS). Here, the systematically sputtered Au thickness optimization procedure revealed noticeable modifications in the graphene Raman spectra and photoluminescence (PL) background quenching, which indicated favorable charge transfer through n-type doping of chemical vapor deposition-grown graphene nanosheets. The highly consistent, individually distributed morphology of the gold nanoislands over graphene nanosheets depicted a reproducibly uniform G-SERS signal with excellent relative standard deviation values (<5%), resulting in the strongest Raman intensity enhancement factors of ∼108 (MB) (methylene blue) and 107 (DPA) (2,6-pyridinedicarboxylic acid) composed of the weakest PL background. The combined charge-transfer-induced chemical enhancement and electromagnetic enhancement from individual Au nanoislands result in a lowering of detectability down to 10-16 M (MB) and 10-11 M (DPA) concentrations with efficient time-dependent signal stability. Additionally, the GAu demonstrated its effective (∼94.4%) photocatalytic degradation capabilities by decomposing MB dye molecules from a concentration of 1 μM to 2.52 fM within 60 min. Therefore, the prominent charge-transfer contribution through controlled Au decoration over graphene nanosheets provides a potential strategy for fabricating superior SERS sensors and photocatalysts exhibiting adequate signal consistency, stability, and photodegradation efficiency through overcoming the limitations of the traditional sensing platforms.
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Affiliation(s)
- Ashwani Kumar Verma
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Jaspal Singh
- Laboratory of Advanced Materials for Energy and Environment, Université Du Québec à Trois-Rivières (UQTR), 3351, Boul. des Forges, C.P. 500, Trois-Rivières, Québec G9A 5H7, Canada
| | - Phuong Nguyen-Tri
- Laboratory of Advanced Materials for Energy and Environment, Université Du Québec à Trois-Rivières (UQTR), 3351, Boul. des Forges, C.P. 500, Trois-Rivières, Québec G9A 5H7, Canada
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Juo JY, Shin BG, Stiepany W, Memmler M, Kern K, Jung SJ. In-situ atomic level observation of the strain response of graphene lattice. Sci Rep 2023; 13:2451. [PMID: 36774393 PMCID: PMC9922254 DOI: 10.1038/s41598-023-29128-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/31/2023] [Indexed: 02/13/2023] Open
Abstract
Strain is inevitable in two-dimensional (2D) materials, regardless of whether the film is suspended or supported. However, the direct measurement of strain response at the atomic scale is challenging due to the difficulties of maintaining both flexibility and mechanical stability at low temperature under UHV conditions. In this work, we have implemented a compact nanoindentation system with a size of [Formula: see text] 160 mm[Formula: see text] [Formula: see text] 5.2 mm in a scanning tunneling microscope (STM) sample holder, which enables the reversible control of strain and gate electric field. A combination of gearbox and piezoelectric actuator allowed us to modulate the depth of the indentation continuously with nanometer precision. The 2D materials were transferred onto the polyimide film. Pd clamp was used to enhance the strain transfer from the polyimide from to the 2D layers. Using this unique technique, strain response of graphene lattice were observed at atomic precision. In the relaxed graphene, strain is induced mainly by local curvature. However, in the strained graphene with tented structure, the lattice parameters become more sensitive to the indentor height change and stretching strain is increased additionally. Moreover, the gate controllability is confirmed by measuring the dependence of the STM tip height on gate voltage.
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Affiliation(s)
- Jz-Yuan Juo
- grid.419552.e0000 0001 1015 6736Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Bong Gyu Shin
- grid.419552.e0000 0001 1015 6736Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany ,grid.264381.a0000 0001 2181 989XSKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 440-746 Republic of Korea
| | - Wolfgang Stiepany
- grid.419552.e0000 0001 1015 6736Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Marko Memmler
- grid.419552.e0000 0001 1015 6736Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Klaus Kern
- grid.419552.e0000 0001 1015 6736Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany ,grid.5333.60000000121839049Institut de Physique, École Poly-technique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Soon Jung Jung
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569, Stuttgart, Germany.
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3
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The Graphene Structure’s Effects on the Current-Voltage and Photovoltaic Characteristics of Directly Synthesized Graphene/n-Si(100) Diodes. NANOMATERIALS 2022; 12:nano12101640. [PMID: 35630863 PMCID: PMC9147930 DOI: 10.3390/nano12101640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 12/04/2022]
Abstract
Graphene was synthesized directly on Si(100) substrates by microwave plasma-enhanced chemical vapor deposition (MW-PECVD). The effects of the graphene structure on the electrical and photovoltaic properties of graphene/n-Si(100) were studied. The samples were investigated using Raman spectroscopy, atomic force microscopy, and by measuring current–voltage (I-V) graphs. The temperature of the hydrogen plasma annealing prior to graphene synthesis was an essential parameter regarding the graphene/Si contact I-V characteristics and photovoltaic parameters. Graphene n-type self-doping was found to occur due to the native SiO2 interlayer at the graphene/Si junction. It was the prevalent cause of the significant decrease in the reverse current and short-circuit current. No photovoltaic effect dependence on the graphene roughness and work function could be observed.
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4
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Luo M, Sun H, Qi Z, Lu K, Chen M, Kang D, Kim Y, Burt D, Yu X, Wang C, Kim YD, Wang H, Wang QJ, Nam D. Triaxially strained suspended graphene for large-area pseudo-magnetic fields. OPTICS LETTERS 2022; 47:2174-2177. [PMID: 35486753 DOI: 10.1364/ol.455569] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 03/26/2022] [Indexed: 05/22/2023]
Abstract
Strain-engineered graphene has garnered much attention recently owing to the possibilities of creating substantial energy gaps enabled by pseudo-magnetic fields (PMFs). While theoretical works proposed the possibility of creating large-area PMFs by straining monolayer graphene along three crystallographic directions, clear experimental demonstration of such promising devices remains elusive. Herein, we experimentally demonstrate a triaxially strained suspended graphene structure that has the potential to possess large-scale and quasi-uniform PMFs. Our structure employs uniquely designed metal electrodes that function both as stressors and metal contacts for current injection. Raman characterization and tight-binding simulations suggest the possibility of achieving PMFs over a micrometer-scale area. Current-voltage measurements confirm an efficient current injection into graphene, showing the potential of our devices for a new class of optoelectronic applications. We also theoretically propose a photonic crystal-based laser structure that obtains strongly localized optical fields overlapping with the spatial area under uniform PMFs, thus presenting a practical route toward the realization of graphene lasers.
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Kim MA, Sorescu DC, Amemiya S, Jordan KD, Liu H. Real-Time Modulation of Hydrogen Evolution Activity of Graphene Electrodes Using Mechanical Strain. ACS APPLIED MATERIALS & INTERFACES 2022; 14:10691-10700. [PMID: 35170299 DOI: 10.1021/acsami.1c21821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This paper reports the effect of mechanically applied elastic strain on the hydrogen evolution reaction (HER) activity of graphene under acidic conditions. An applied tensile strain of 0.2% on a graphene electrode is shown to lead to a 1-3% increase in the HER current. The tensile strain increases HER activity, whereas compressive strain decreases it. Density functional theory (DFT) calculations using a periodic graphene slab model predict an increase in the adsorption energy of the H atom with growing tensile strain, consistent with an enhancement of the current density in HER, similar to that observed experimentally.
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Affiliation(s)
- Min A Kim
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Dan C Sorescu
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236, United States
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Shigeru Amemiya
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Kenneth D Jordan
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Haitao Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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Mazaheri L, Jelken J, Avilés MO, Legge S, Lagugné-Labarthet F. Investigating the Performances of Wide-Field Raman Microscopy with Stochastic Optical Reconstruction Post-Processing. APPLIED SPECTROSCOPY 2022; 76:340-351. [PMID: 35128956 PMCID: PMC8915227 DOI: 10.1177/00037028211056975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/07/2021] [Indexed: 05/25/2023]
Abstract
Super-resolution fluorescence microscopy based on localization algorithms has tremendously impacted the field of imaging by improving the spatial resolution of optical measurements with specific blinking fluorophores and concomitant reduction of acquisition time. In vibrational spectroscopy and imaging, various methods have been developed to surpass the diffraction limit including near-field scattering methods, such as in tip-enhanced Raman and infrared spectroscopies. Although these scanning-probe techniques can provide exquisite spatial resolution, they often require long acquisition times and tedious fabrication of nano-scale scanning probes. Herein, stochastic optical reconstruction microscopy (STORM) protocol is applied on Raman measurements acquired using a wide-field home-built microscopy setup. We explore how the fluctuations of the Raman signal acquired over a series of time-lapse images at specific spectral ranges can be exploited with STORM processing, possibly revealing details with improved spatial resolution, under lower irradiance and with faster acquisition speed that cannot be achieved in point scanning mode over the same field of view. Samples studied here include patterned silicon, polystyrene microspheres on a silicon wafer, and graphene on a silicon/silicon dioxide substrate. The outcome presents an effective way to collect Raman images at selected spectral ranges with spatial resolutions of ∼200 nm over a large field of view under 532 nm excitation together with an acquisition speed improved by two orders of magnitude and under a significantly reduced irradiance compared to confocal laser scanning acquisition.
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Affiliation(s)
| | | | | | | | - François Lagugné-Labarthet
- François Lagugné-Labarthet, Department of Chemistry, The Centre for Advanced Materials and Biomaterials Research (CAMBR), The University of Western Ontario (Western University), 1151 Richmond St., London, ON N6A 5B7, Canada.
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7
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Kalosakas G, Lathiotakis NN, Papagelis K. Uniaxially Strained Graphene: Structural Characteristics and G-Mode Splitting. MATERIALS (BASEL, SWITZERLAND) 2021; 15:67. [PMID: 35009214 PMCID: PMC8746274 DOI: 10.3390/ma15010067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
The potential use of graphene in various strain engineering applications requires an accurate characterization of its properties when the material is under different mechanical loads. In this work, we present the strain dependence of the geometrical characteristics at the atomic level and the Raman active G-band evolution in a uniaxially strained graphene monolayer, using density functional theory methods as well as molecular dynamics atomistic simulations for strains that extend up to the structural failure. The bond length and bond angle variations with strain, applied either along the zigzag or along the armchair direction, are discussed and analytical relations describing this dependence are provided. The G-mode splitting with strain, as obtained by first principles' methods, is also presented. While for small strains, up to around 1%, the G-band splitting is symmetrical in the two perpendicular directions of tension considered here, this is no longer the case for larger values of strains where the splitting appears to be larger for strains along the zigzag direction. Further, a crossing is observed between the lower frequency split G-mode component and the out-of-plane optical mode at the Γ point for large uniaxial strains (>20%) along the zigzag direction.
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Affiliation(s)
- George Kalosakas
- Department of Materials Science, University of Patras, GR-26504 Rio, Greece
| | - Nektarios N. Lathiotakis
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Vass. Constantinou 48, GR-11634 Athens, Greece;
| | - Konstantinos Papagelis
- Department of Solid State Physics, School of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece;
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8
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Nano-Physical Characterization of Chemical Vapor Deposition-Grown Monolayer Graphene for High Performance Electrode: Raman, Surface-Enhanced Raman Spectroscopy, and Electrostatic Force Microscopy Studies. NANOMATERIALS 2021; 11:nano11112839. [PMID: 34835607 PMCID: PMC8623610 DOI: 10.3390/nano11112839] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/12/2021] [Accepted: 10/20/2021] [Indexed: 11/16/2022]
Abstract
To achieve high-quality chemical vapor deposition of monolayer graphene electrodes (CVD-MG), appropriate characterization at each fabrication step is essential. In this article, (1) Raman spectroscopy/microscopy are employed to unravel the contact effect between the CVD-MG and Cu foil in suspended/supported formation. (2) The Surface-Enhanced Raman spectroscopy (SERS) system is described, unveiling the presence of a z-directional radial breathing-like mode (RBLM) around 150 cm-1, which matches the Raman shift of the radial breathing mode (RBM) from single-walled carbon nanotubes (SWCNTs) around 150 cm-1. This result indicates the CVD-MG located between the Au NPs and Au film is not flat but comprises heterogeneous protrusions of some domains along the z-axis. Consequently, the degree of carrier mobility can be influenced, as the protruding domains result in lower carrier mobility due to flexural phonon-electron scattering. A strongly enhanced G-peak domain, ascribed to the presence of scrolled graphene nanoribbons (sGNRs), was observed, and there remains the possibility for the fabrication of sGNRs as sources of open bandgap devices. (3) Electrostatic force microscopy (EFM) is used for the measurement of surface charge distribution of graphene at the nanoscale and is crucial in substantiating the electrical performance of CVD-MG, which was influenced by the surface structure of the Cu foil. The ripple (RP) structures were determined using EFM correlated with Raman spectroscopy, exhibiting a higher tapping amplitude which was observed with structurally stable and hydrophobic RPs with a threading type than surrounding RPs. (4) To reduce the RP density and height, a plausible fabrication could be developed that controls the electrical properties of the CVD-MG by tuning the cooling rate.
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9
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Influences of Initial Surface Conditions on Response Characteristics of Amorphous Silicon Films to Nanosecond Laser Irradiation. MICROMACHINES 2021; 12:mi12070807. [PMID: 34357217 PMCID: PMC8307301 DOI: 10.3390/mi12070807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 06/28/2021] [Accepted: 07/07/2021] [Indexed: 01/17/2023]
Abstract
Although laser-produced micro-/nano-structures have been extensively studied, the effects of the initial surface conditions on the formed micro-/nano-structures have rarely been investigated. In this study, through nanosecond pulsed laser irradiation of unpolished and polished amorphous silicon films, entirely different surface characteristics were observed. The effects of laser irradiation parameters, such as repetition frequency, beam overlap ratio, and scanning velocity, on the surface characteristics were investigated, followed by the characterization of surface roughness, energy-dispersive X-ray spectroscopy, and Raman spectroscopy of the irradiated surfaces. For the unpolished surface, novel micro-protrusions were generated after laser irradiation, whereas no such micro-protrusions were formed on the polished surface. The experimental results indicated that the height of the micro-protrusions could be tuned using laser irradiation parameters and that laser irradiation promoted the crystallization of the amorphous silicon film. Moreover, the formation mechanism of the micro-protrusions was linked to fluctuations of the solid–liquid interface caused by continuous laser pulse shocks at higher repetition frequencies. The findings of this study suggest important correlations between the initial surface conditions and micro-/nano-structure formation, which may enhance our fundamental understanding of the formation of micro-/nano-structures.
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10
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Castagnola E, Garg R, Rastogi SK, Cohen-Karni T, Cui XT. 3D fuzzy graphene microelectrode array for dopamine sensing at sub-cellular spatial resolution. Biosens Bioelectron 2021; 191:113440. [PMID: 34171734 DOI: 10.1016/j.bios.2021.113440] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/28/2021] [Accepted: 06/13/2021] [Indexed: 02/07/2023]
Abstract
The development of a high sensitivity real-time sensor for multi-site detection of dopamine (DA) with high spatial and temporal resolution is of fundamental importance to study the complex spatial and temporal pattern of DA dynamics in the brain, thus improving the understanding and treatments of neurological and neuropsychiatric disorders. In response to this need, here we present high surface area out-of-plane grown three-dimensional (3D) fuzzy graphene (3DFG) microelectrode arrays (MEAs) for highly selective, sensitive, and stable DA electrochemical sensing. 3DFG microelectrodes present a remarkable sensitivity to DA (2.12 ± 0.05 nA/nM, with LOD of 364.44 ± 8.65 pM), the highest reported for nanocarbon MEAs using Fast Scan Cyclic Voltammetry (FSCV). The high surface area of 3DFG allows for miniaturization of electrode down to 2 × 2 μm2, without compromising the electrochemical performance. Moreover, 3DFG MEAs are electrochemically stable under 7.2 million scans of continuous FSCV cycling, present exceptional selectivity over the most common interferents in vitro with minimum fouling by electrochemical byproducts and can discriminate DA and serotonin (5-HT) in response to the injection of their 50:50 mixture. These results highlight the potential of 3DFG MEAs as a promising platform for FSCV based multi-site detection of DA with high sensitivity, selectivity, and spatial resolution.
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Affiliation(s)
- Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260 Pittsburgh, PA, USA
| | - Raghav Garg
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Sahil K Rastogi
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Tzahi Cohen-Karni
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA; Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive Pittsburgh, PA, 15219-3110, USA.
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, 3501 Fifth Ave. Pittsburgh, PA 15260 Pittsburgh, PA, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive Pittsburgh, PA, 15219-3110, USA; Center for Neural Basis of Cognition, University of Pittsburgh, 4400 Fifth Ave, Pittsburgh, PA 15213, Pittsburgh, PA, 15261, USA.
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11
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Vinchon P, Glad X, Robert Bigras G, Martel R, Stafford L. Preferential self-healing at grain boundaries in plasma-treated graphene. NATURE MATERIALS 2021; 20:49-54. [PMID: 32690911 DOI: 10.1038/s41563-020-0738-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Engineering of defects located in grains or at grain boundaries is central to the development of functional materials. Although there is a surge of interest in the formation, migration and annihilation of defects during ion and plasma irradiation of bulk materials, these processes are rarely assessed in low-dimensional materials and remain mostly unexplored spectroscopically at the micrometre scale due to experimental limitations. Here, we use a hyperspectral Raman imaging scheme providing high selectivity and diffraction-limited spatial resolution to examine plasma-induced damage in a polycrystalline graphene film. Measurements conducted before and after very low-energy (11-13 eV) ion bombardment show defect generation in graphene grains following a zero-dimensional defect curve, whereas domain boundaries tend to develop as one-dimensional defects. Damage generation is slower at grain boundaries than within the grains, a behaviour ascribed to preferential self-healing. This evidence of local defect migration and structural recovery in graphene sheds light on the complexity of chemical and physical processes at the grain boundaries of two-dimensional materials.
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Affiliation(s)
- P Vinchon
- Département de Physique, Université de Montréal, Montréal, Québec, Canada
| | - X Glad
- Département de Physique, Université de Montréal, Montréal, Québec, Canada
| | - G Robert Bigras
- Département de Physique, Université de Montréal, Montréal, Québec, Canada
| | - R Martel
- Département de Chimie, Université de Montréal, Montréal, Québec, Canada
| | - L Stafford
- Département de Physique, Université de Montréal, Montréal, Québec, Canada.
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12
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Robert Bigras G, Vinchon P, Allard C, Glad X, Martel R, Stafford L. Probing plasma-treated graphene using hyperspectral Raman. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:063903. [PMID: 32611065 DOI: 10.1063/5.0006556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/26/2020] [Indexed: 06/11/2023]
Abstract
Raman spectroscopy provides rich optical signals that can be used, after data analysis, to assess if a graphene layer is pristine, doped, damaged, functionalized, or stressed. The area being probed by a conventional Raman spectrometer is, however, limited to the size of the laser beam (∼1 µm); hence, detailed mapping of inhomogeneities in a graphene sample requires slow and sequential acquisition of a Raman spectrum at each pixel. Studies of physical and chemical processes on polycrystalline and heterogeneous graphene films require more advanced hyperspectral Raman capable of fast imaging at a high spatial resolution over hundreds of microns. Here, we compare the capacity of two different Raman imaging schemes (scanning and global) to probe graphene films modified by a low-pressure plasma treatment and present an analysis method providing assessments of the surface properties at local defects, grain boundaries, and other heterogeneities. By comparing statistically initial and plasma-treated regions of graphene, we highlight the presence of inhomogeneities after plasma treatment linked to the initial state of the graphene surface. These results provided statistical results on the correlation between the graphene initial state and the corresponding graphene-plasma interaction. This work further demonstrates the potential use of global hyperspectral Raman imaging with advanced Raman spectra analysis to study graphene physics and chemistry on a scale of hundreds of microns.
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Affiliation(s)
- G Robert Bigras
- Département de Physique, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2V 0B3, Canada
| | - P Vinchon
- Département de Physique, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2V 0B3, Canada
| | - C Allard
- Département de Chimie, Université de Montréal, 5155 Chemin de la Rampe, Montréal, Québec H3T 1J4, Canada
| | - X Glad
- Département de Physique, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2V 0B3, Canada
| | - R Martel
- Département de Chimie, Université de Montréal, 5155 Chemin de la Rampe, Montréal, Québec H3T 1J4, Canada
| | - L Stafford
- Département de Physique, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec H2V 0B3, Canada
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Transferless Inverted Graphene/Silicon Heterostructures Prepared by Plasma-Enhanced Chemical Vapor Deposition of Amorphous Silicon on CVD Graphene. NANOMATERIALS 2020; 10:nano10030589. [PMID: 32213885 PMCID: PMC7153506 DOI: 10.3390/nano10030589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/19/2020] [Accepted: 03/19/2020] [Indexed: 11/25/2022]
Abstract
The heterostructures of two-dimensional (2D) and three-dimensional (3D) materials represent one of the focal points of current nanotechnology research and development. From an application perspective, the possibility of a direct integration of active 2D layers with exceptional optoelectronic and mechanical properties into the existing semiconductor manufacturing processes is extremely appealing. However, for this purpose, 2D materials should ideally be grown directly on 3D substrates to avoid the transferring step, which induces damage and contamination of the 2D layer. Alternatively, when such an approach is difficult—as is the case of graphene on noncatalytic substrates such as Si—inverted structures can be created, where the 3D material is deposited onto the 2D substrate. In the present work, we investigated the possibility of using plasma-enhanced chemical vapor deposition (PECVD) to deposit amorphous hydrogenated Si (a-Si:H) onto graphene resting on a catalytic copper foil. The resulting stacks created at different Si deposition temperatures were investigated by the combination of Raman spectroscopy (to quantify the damage and to estimate the change in resistivity of graphene), temperature-dependent dark conductivity, and constant photocurrent measurements (to monitor the changes in the electronic properties of a-Si:H). The results indicate that the optimum is 100 °C deposition temperature, where the graphene still retains most of its properties and the a-Si:H layer presents high-quality, device-ready characteristics.
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14
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Rhee D, Paci JT, Deng S, Lee WK, Schatz GC, Odom TW. Soft Skin Layers Enable Area-Specific, Multiscale Graphene Wrinkles with Switchable Orientations. ACS NANO 2020; 14:166-174. [PMID: 31675210 DOI: 10.1021/acsnano.9b06325] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This paper reports a method to realize crack-free graphene wrinkles with variable spatial wavelengths and switchable orientations. Graphene supported on a thin fluoropolymer and prestrained elastomer substrate can exhibit conformal wrinkling after strain relief. The wrinkle orientation could be switched beyond the intrinsic fracture limit of graphene for hundreds of cycles of stretching and releasing without forming cracks. Mechanical modeling revealed that the fluoropolymer layer mediated the structural evolution of the graphene wrinkles without crack formation or delamination. Patterned fluoropolymer layers with different thicknesses produced wrinkles with controlled wavelengths and orientations while maintaining the mechanical integrity of graphene under high tensile strain.
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Affiliation(s)
| | - Jeffrey T Paci
- Department of Chemistry , University of Victoria , Victoria , British Columbia V8P 5C2 , Canada
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Sakai K, Teshima TF, Nakashima H, Ueno Y. Graphene-based neuron encapsulation with controlled axonal outgrowth. NANOSCALE 2019; 11:13249-13259. [PMID: 31149690 DOI: 10.1039/c9nr04165f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Neuronal constructs with tuneable 3D geometry can contribute greatly to the construction of brain-like functional tissues for transplantable grafts and robust experimental models. In this study, we propose a self-folding graphene/polymer bilayer film that forms a micro-roll for neuron encapsulation, and highlight the importance of employing pores on the micro-roll to allow neurons to interact with their surroundings. The micro-patterns and varied thicknesses of the bilayer provide control over the 3D geometries of the micro-roll. The pores facilitate the diffusion of reagents, resulting in the adequate loading of probes for imaging and the successful stimulation of the encapsulated neurons. Moreover, the encapsulated neurons inside the micro-roll are functionally integrated into surrounding neuronal networks by extending their axons through the pores. Thus, our method for encapsulating neurons with a porous graphene-laden film allows the construction of precisely shaped neuronal tissues that interact with their surroundings. We believe that the method will open a new avenue for the reconstruction of functional neuronal tissues and is potentially applicable to other self-folding bilayers.
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Affiliation(s)
- Koji Sakai
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
| | - Tetsuhiko F Teshima
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
| | - Hiroshi Nakashima
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
| | - Yuko Ueno
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
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16
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Raman Study of Strain Relaxation from Grain Boundaries in Epitaxial Graphene Grown by Chemical Vapor Deposition on SiC. NANOMATERIALS 2019; 9:nano9030372. [PMID: 30841583 PMCID: PMC6473967 DOI: 10.3390/nano9030372] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 02/25/2019] [Accepted: 03/01/2019] [Indexed: 11/16/2022]
Abstract
Strains in graphene play a significant role in graphene-based electronics, but many aspects of the grain boundary effects on strained graphene remain unclear. Here, the relationship between grain boundary and strain property of graphene grown by chemical vapor deposition (CVD) on the C-face of SiC substrate has been investigated by Raman spectroscopy. It is shown that abundant boundary-like defects exist in the graphene film and the blue-shifted 2D-band frequency, which results from compressive strain in graphene film, shifts downward linearly as 1/La increases. Strain relaxation caused by grain boundary diffusion is considered to be the reason and the mechanism is analyzed in detail.
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17
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Teshima TF, Henderson CS, Takamura M, Ogawa Y, Wang S, Kashimura Y, Sasaki S, Goto T, Nakashima H, Ueno Y. Self-Folded Three-Dimensional Graphene with a Tunable Shape and Conductivity. NANO LETTERS 2019; 19:461-470. [PMID: 30525693 DOI: 10.1021/acs.nanolett.8b04279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Three-dimensional (3D) graphene architectures are of great interest as applications in flexible electronics and biointerfaces. In this study, we demonstrate the facile formation of predetermined 3D polymeric microstructures simply by transferring monolayer graphene. The graphene adheres to the surface of polymeric films via noncovalent π-π stacking bonding and induces a sloped internal strain, leading to the self-rolling of 3D microscale architectures. Micropatterns and varied thicknesses of the 2D films prior to the self-rolling allows for control over the resulting 3D geometries. The strain then present on the hexagonal unit cell of the graphene produces a nonlinear electrical conductivity across the device. The driving force behind the self-folding process arises from the reconfiguration of the molecules within the crystalline materials. We believe that this effective and versatile way of realizing a 3D graphene structure is potentially applicable to alternative 2D layered materials as well as other flexible polymeric templates.
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Affiliation(s)
- Tetsuhiko F Teshima
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Calum S Henderson
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
- School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh , Scotland EH9 3FJ, United Kingdom
| | - Makoto Takamura
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Yui Ogawa
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Shengnan Wang
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Yoshiaki Kashimura
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Satoshi Sasaki
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Toichiro Goto
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Hiroshi Nakashima
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
| | - Yuko Ueno
- NTT Basic Research Laboratories , NTT Corporation , 3-1 Morinosato Wakamiya , Atsugi , Kanagawa 243-0198 , Japan
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18
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Polyhydroxybutyrate-co-hydroxyvalerate copolymer modified graphite oxide based 3D scaffold for tissue engineering application. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 94:534-546. [PMID: 30423738 DOI: 10.1016/j.msec.2018.10.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 09/10/2018] [Accepted: 10/02/2018] [Indexed: 11/22/2022]
Abstract
In this study, we have fabricated the PHBV functionalized graphite oxide using freeze drying technique, followed by 'in situ' pay loading of Fe3O4 nanoparticles onto the hydrophobic plate of the composite basal plane; thereby, mechanically and thermally stable, bio-imaging Fe3O4/GO-g-PHBV composites have been developed. The synthesis of Fe3O4/GO-g-PHBV composite was confirmed by field emission SEM and TEM analyses, X-ray diffraction and Fourier transform infrared spectroscopy. The wrapping of PHBV copolymer into the graphene layers was investigated by atomic force microscopy and Raman spectral analyses which provided the shifting of the 2D band with low signal intensity in the range of 2600-3000 cm-1. The bactericidal activities of the Fe3O4/GO-g-PHBV composite films were found to exhibit more efficiency against Gram-negative bacteria strains compared to Gram-positive strains. In vibrating sample magnetometer (VSM) analysis, the zero value of coercivity revealed the super-paramagnetic nature of the Fe3O4/GO-g-PHBV composites. The Phantom agar magnetic resonance imaging analysis revealed the efficiency of Fe3O4 nanoparticles as a negative contrast (T2 contrast) along with higher relaxivity value. The significant fibroblast cell (NIH 3T3) adhesion and proliferation (85%) on the Fe3O4/GO-g-PHBV composite surface indicated the physiological and biocompatible stability of that composite along with the presence of large π conjugated aromatic domain.
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19
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Sarwat SG, Tweedie M, Porter BF, Zhou Y, Sheng Y, Mol J, Warner J, Bhaskaran H. Revealing Strain-Induced Effects in Ultrathin Heterostructures at the Nanoscale. NANO LETTERS 2018; 18:2467-2474. [PMID: 29510053 DOI: 10.1021/acs.nanolett.8b00036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two-dimensional materials are being increasingly studied, particularly for flexible and wearable technologies because of their inherent thickness and flexibility. Crucially, one aspect where our understanding is still limited is on the effect of mechanical strain, not on individual sheets of materials, but when stacked together as heterostructures in devices. In this paper, we demonstrate the use of Kelvin probe microscopy in capturing the influence of uniaxial tensile strain on the band-structures of graphene and WS2 (mono- and multilayered) based heterostructures at high resolution. We report a major advance in strain characterization tools through enabling a single-shot capture of strain defined changes in a heterogeneous system at the nanoscale, overcoming the limitations (materials, resolution, and substrate effects) of existing techniques such as optical spectroscopy. Using this technique, we observe that the work-functions of graphene and WS2 increase as a function of strain, which we attribute to the Fermi level lowering from increased p-doping. We also extract the nature of the interfacial heterojunctions and find that they get strongly modulated from strain. We observe that the strain-enhanced charge transfer with the substrate plays a dominant role, causing the heterostructures to behave differently from two-dimensional materials in their isolated forms.
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Affiliation(s)
- Syed Ghazi Sarwat
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Martin Tweedie
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Benjamin F Porter
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Yingqiu Zhou
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Yuewen Sheng
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Jan Mol
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Jamie Warner
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
| | - Harish Bhaskaran
- Department of Materials , University of Oxford , Oxford OX1 3PH , United Kingdom
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20
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Jeon I, Yoon J, Ahn N, Atwa M, Delacou C, Anisimov A, Kauppinen EI, Choi M, Maruyama S, Matsuo Y. Carbon Nanotubes versus Graphene as Flexible Transparent Electrodes in Inverted Perovskite Solar Cells. J Phys Chem Lett 2017; 8:5395-5401. [PMID: 28994283 DOI: 10.1021/acs.jpclett.7b02229] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Transparent carbon electrodes, carbon nanotubes, and graphene were used as the bottom electrode in flexible inverted perovskite solar cells. Their photovoltaic performance and mechanical resilience were compared and analyzed using various techniques. Whereas a conventional inverted perovskite solar cells using indium tin oxide showed a power conversion efficiency of 17.8%, the carbon nanotube- and graphene-based cells showed efficiencies of 12.8% and 14.2%, respectively. An established MoO3 doping was used for carbon electrode-based devices. The difference in the photovoltaic performance between the carbon nanotube- and graphene-based cells was due to the difference in morphology and transmittance. Raman spectroscopy, and cyclic flexural testing revealed that the graphene-based cells were more susceptible to strain than the carbon nanotube-based cells, though the difference was marginal. Overall, despite higher performance, the transfer step for graphene has lower reproducibility. Thus, the development of better graphene transfer methods would help maximize the current capacity of graphene-based cells.
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Affiliation(s)
- Il Jeon
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-8656, Japan
| | - Jungjin Yoon
- Department of Mechanical and Aerospace Engineering, Seoul National University , Seoul 08826, South Korea
| | - Namyoung Ahn
- Department of Mechanical and Aerospace Engineering, Seoul National University , Seoul 08826, South Korea
| | - Mohamed Atwa
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-8656, Japan
| | - Clement Delacou
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-8656, Japan
| | - Anton Anisimov
- Canatu, Ltd. , Konalankuja 5, FI-00390 Helsinki, Finland
| | - Esko I Kauppinen
- Department of Applied Physics, Aalto University School of Science , FI-00076 Aalto, Finland
| | - Mansoo Choi
- Department of Mechanical and Aerospace Engineering, Seoul National University , Seoul 08826, South Korea
| | - Shigeo Maruyama
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-8656, Japan
- Energy Nano Engineering Laboratory, National Institute of Advanced Industrial Science and Technology (AIST) , Ibaraki 305-8564, Japan
| | - Yutaka Matsuo
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-8656, Japan
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China , Anhui 230026, China
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21
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Lee WK, Kang J, Chen KS, Engel CJ, Jung WB, Rhee D, Hersam MC, Odom TW. Multiscale, Hierarchical Patterning of Graphene by Conformal Wrinkling. NANO LETTERS 2016; 16:7121-7127. [PMID: 27726404 DOI: 10.1021/acs.nanolett.6b03415] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This paper describes how delamination-free, hierarchical patterning of graphene can be achieved on prestrained thermoplastic sheets by surface wrinkling. Conformal contact between graphene and the substrate during strain relief was maintained by the presence of a soft skin layer, resulting in the uniform patterning of three-dimensional wrinkles over large areas (>cm2). The graphene wrinkle wavelength was tuned from the microscale to the nanoscale by controlling the thickness of the skin layer with 1 nm accuracy to realize a degree of control not possible by crumpling, which relies on delamination. Hierarchical patterning of the skin layers with varying thicknesses enabled multiscale graphene wrinkles with predetermined orientations to be formed. Significantly, hierarchical graphene wrinkles exhibited tunable mechanical stiffness at the nanoscale without compromising the macroscale electrical conductivity.
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Affiliation(s)
- Won-Kyu Lee
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Junmo Kang
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Kan-Sheng Chen
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Clifford J Engel
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Woo-Bin Jung
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Dongjoon Rhee
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Mark C Hersam
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
| | - Teri W Odom
- Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States
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22
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da Cunha Rodrigues G, Zelenovskiy P, Romanyuk K, Luchkin S, Kopelevich Y, Kholkin A. Correspondence: Reply to 'On the nature of strong piezoelectricity in graphene on SiO2'. Nat Commun 2016; 7:11571. [PMID: 27187896 PMCID: PMC4873649 DOI: 10.1038/ncomms11571] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Gonçalo da Cunha Rodrigues
- Department of Physics &CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Pavel Zelenovskiy
- Institute of Natural Sciences, Ural Federal University, Ekaterinburg 620000, Russia
| | - Konstantin Romanyuk
- Department of Physics &CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.,Institute of Natural Sciences, Ural Federal University, Ekaterinburg 620000, Russia
| | - Sergey Luchkin
- Department of Physics &CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Yakov Kopelevich
- Instituto de Física, UNICAMP, Campinas, São Paulo 13083-859, Brasil
| | - Andrei Kholkin
- Department of Physics &CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.,Institute of Natural Sciences, Ural Federal University, Ekaterinburg 620000, Russia
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23
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Stampfer C, Reichardt S. Correspondence: On the nature of strong piezoelectricity in graphene on SiO2. Nat Commun 2016; 7:11570. [PMID: 27187723 PMCID: PMC4873625 DOI: 10.1038/ncomms11570] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Christoph Stampfer
- JARA-FIT and 2nd Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany.,Peter Grünberg Institute (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Sven Reichardt
- JARA-FIT and 2nd Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany.,Physics and Material Science Research Unit, Université du Luxembourg, 1511 Luxembourg, Luxembourg
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24
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Li Z, Kinloch IA, Young RJ, Novoselov KS, Anagnostopoulos G, Parthenios J, Galiotis C, Papagelis K, Lu CY, Britnell L. Deformation of wrinkled graphene. ACS NANO 2015; 9:3917-25. [PMID: 25765609 PMCID: PMC4424820 DOI: 10.1021/nn507202c] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 03/12/2015] [Indexed: 05/21/2023]
Abstract
The deformation of monolayer graphene, produced by chemical vapor deposition (CVD), on a polyester film substrate has been investigated through the use of Raman spectroscopy. It has been found that the microstructure of the CVD graphene consists of a hexagonal array of islands of flat monolayer graphene separated by wrinkled material. During deformation, it was found that the rate of shift of the Raman 2D band wavenumber per unit strain was less than 25% of that of flat flakes of mechanically exfoliated graphene, whereas the rate of band broadening per unit strain was about 75% of that of the exfoliated material. This unusual deformation behavior has been modeled in terms of mechanically isolated graphene islands separated by the graphene wrinkles, with the strain distribution in each graphene island determined using shear lag analysis. The effect of the size and position of the Raman laser beam spot has also been incorporated in the model. The predictions fit well with the behavior observed experimentally for the Raman band shifts and broadening of the wrinkled CVD graphene. The effect of wrinkles upon the efficiency of graphene to reinforce nanocomposites is also discussed.
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Affiliation(s)
- Zheling Li
- School of Materials, School of Physics and Astronomy, and BGT Materials Ltd., Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Ian A. Kinloch
- School of Materials, School of Physics and Astronomy, and BGT Materials Ltd., Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Robert J. Young
- School of Materials, School of Physics and Astronomy, and BGT Materials Ltd., Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
- Address correspondence to
| | - Kostya S. Novoselov
- School of Materials, School of Physics and Astronomy, and BGT Materials Ltd., Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - George Anagnostopoulos
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology − Hellas (FORTH/ICE-HT), P.O. Box 1414, Patras 26504, Greece
| | - John Parthenios
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology − Hellas (FORTH/ICE-HT), P.O. Box 1414, Patras 26504, Greece
| | - Costas Galiotis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology − Hellas (FORTH/ICE-HT), P.O. Box 1414, Patras 26504, Greece
- Department of Chemical Engineering and Department of Materials Science, University of Patras, Patras 26504, Greece
| | - Konstantinos Papagelis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology − Hellas (FORTH/ICE-HT), P.O. Box 1414, Patras 26504, Greece
- Department of Chemical Engineering and Department of Materials Science, University of Patras, Patras 26504, Greece
| | - Ching-Yu Lu
- School of Materials, School of Physics and Astronomy, and BGT Materials Ltd., Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Liam Britnell
- School of Materials, School of Physics and Astronomy, and BGT Materials Ltd., Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
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25
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Abstract
The mechanical properties of 2D materials such as monolayer graphene are of extreme importance for several potential applications. We summarize the experimental and theoretical results to date on mechanical loading of freely suspended or fully supported graphene. We assess the obtained axial properties of the material in tension and compression and comment on the methods used for deriving the various reported values. We also report on past and current efforts to define the elastic constants of graphene in a 3D representation. Current areas of research that are concerned with the effect of production method and/or the presence of defects upon the mechanical integrity of graphene are also covered. Finally, we examine extensively the work related to the effect of graphene deformation upon its electronic properties and the possibility of employing strained graphene in future electronic applications.
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Affiliation(s)
- Costas Galiotis
- Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), 26504 Patras, Greece; , ,
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26
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Ago H, Endo H, Solís-Fernández P, Takizawa R, Ohta Y, Fujita Y, Yamamoto K, Tsuji M. Controlled van der Waals epitaxy of monolayer MoS2 triangular domains on graphene. ACS APPLIED MATERIALS & INTERFACES 2015; 7:5265-73. [PMID: 25695865 DOI: 10.1021/am508569m] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Multilayered heterostructures of two-dimensional materials have recently attracted increased interest because of their unique electronic and optical properties. Here, we present chemical vapor deposition (CVD) growth of triangular crystals of monolayer MoS2 on single-crystalline hexagonal graphene domains which are also grown by CVD. We found that MoS2 grows selectively on the graphene domains rather than on the bare supporting SiO2 surface. Reflecting the heteroepitaxy of the growth process, the MoS2 domains grown on graphene present two preferred equivalent orientations. The interaction between the MoS2 and the graphene induced an upshift of the Raman G and 2D bands of the graphene, while significant photoluminescence quenching was observed for the monolayer MoS2. Furthermore, photoinduced current modulation along with an optical memory effect was demonstrated for the MoS2-graphene heterostructure. Our work highlights that heterostructures synthesized by CVD offer an effective interlayer van der Waals interaction which can be developed for large-area multilayer electronic and photonic devices.
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Affiliation(s)
- Hiroki Ago
- Institute for Materials Chemistry and Engineering (IMCE) and ‡Graduate School of Engineering Sciences, Kyushu University , Fukuoka 816-8580, Japan
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27
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Wood JD, Doidge GP, Carrion EA, Koepke JC, Kaitz JA, Datye I, Behnam A, Hewaparakrama J, Aruin B, Chen Y, Dong H, Haasch RT, Lyding JW, Pop E. Annealing free, clean graphene transfer using alternative polymer scaffolds. NANOTECHNOLOGY 2015; 26:055302. [PMID: 25580991 DOI: 10.1088/0957-4484/26/5/055302] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We examine the transfer of graphene grown by chemical vapor deposition (CVD) with polymer scaffolds of poly(methyl methacrylate) (PMMA), poly(lactic acid) (PLA), poly(phthalaldehyde) (PPA), and poly(bisphenol A carbonate) (PC). We find that optimally reactive PC scaffolds provide the cleanest graphene transfers without any annealing, after extensive comparison with optical microscopy, x-ray photoelectron spectroscopy, atomic force microscopy, and scanning tunneling microscopy. Comparatively, films transferred with PLA, PPA, PMMA/PC, and PMMA have a two-fold higher roughness and a five-fold higher chemical doping. Using PC scaffolds, we demonstrate the clean transfer of CVD multilayer graphene, fluorinated graphene, and hexagonal boron nitride. Our annealing free, PC transfers enable the use of atomically-clean nanomaterials in biomolecule encapsulation and flexible electronic applications.
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Affiliation(s)
- Joshua D Wood
- Dept. of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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28
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Ge S, Lan F, Yu F, Yu J. Applications of graphene and related nanomaterials in analytical chemistry. NEW J CHEM 2015. [DOI: 10.1039/c4nj01783h] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Graphene and its related materials remain a very bright and exciting prospect in analytical chemistry.
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Affiliation(s)
- Shenguang Ge
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan)
- School of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
| | - Feifei Lan
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan)
- School of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
| | - Feng Yu
- Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan
- School of Chemistry and Chemical Engineering
- Shihezi University
- Shihezi 832003
- China
| | - Jinghua Yu
- Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan)
- School of Chemistry and Chemical Engineering
- University of Jinan
- Jinan 250022
- China
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29
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Tip-Enhanced Raman Scattering of Nanomaterials. E-JOURNAL OF SURFACE SCIENCE AND NANOTECHNOLOGY 2015. [DOI: 10.1380/ejssnt.2015.329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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30
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Pan SH, Medina H, Wang SB, Chou LJ, Wang ZM, Chen KH, Chen LC, Chueh YL. Direct assessment of the mechanical modulus of graphene co-doped with low concentrations of boron-nitrogen by a non-contact approach. NANOSCALE 2014; 6:8635-8641. [PMID: 24882359 DOI: 10.1039/c4nr00495g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Boron and nitrogen co-doping has been shown to be an effective way to induce a band gap in graphene for electrical applications but only a few theoretical studies have been done to understand the elastic and mechanical properties of the modified graphene. Until now, no experimental assessment of the mechanical modulus of boron-nitrogen-doped graphene (BNG) has been reported in the literature. Here, we demonstrate a novel non-contact approach to determine the in-plane stiffness of BNG at low BN concentrations. The in-plane stiffness of BNG with 2 at% BN concentration was estimated to be about 309 N m(-1), which is lower than that of pristine graphene, in good agreement with some theoretical studies. Moreover, we correlated the conductivity of BNG with induced strain and found the BNG to be more sensitive than pristine graphene in response to externally applied strain. This result indicates that BNG is a more suitable material than graphene for strain sensor applications.
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Affiliation(s)
- Shun-Hsien Pan
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan.
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31
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Ogawa Y, Komatsu K, Kawahara K, Tsuji M, Tsukagoshi K, Ago H. Structure and transport properties of the interface between CVD-grown graphene domains. NANOSCALE 2014; 6:7288-7294. [PMID: 24847777 DOI: 10.1039/c3nr06828e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
During the chemical vapor deposition (CVD) growth of graphene, graphene domains grown on a Cu surface merge together and form a uniform graphene sheet. For high-performance electronics and other applications, it is important to understand the interfacial structure of the merged domains, as well as their influence on the physical properties of graphene. We synthesized large hexagonal graphene domains with controlled orientations on a heteroepitaxial Cu film and studied the structure and properties of the interfaces between the domains mainly merged with the same angle. Although the merged domains have various interfaces with/without wrinkles and/or increased defect-related Raman D-band intensity, the intra-domain transport showed higher carrier mobility reaching 20,000 cm(2) V(-1) s(-1) on SiO2 at 280 K (the mean value was 7200 cm(2) V(-1) s(-1)) than that measured for inter-domain areas, 6400 cm(2) V(-1) s(-1) (mean value 2000 cm(2) V(-1) s(-1)). The temperature dependence of the mobility suggests that impurity scattering dominates at the interface even for the merged domains with the same orientation. This study highlights the importance of domain interfaces, especially on the carrier transport properties, in CVD-grown graphene.
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Affiliation(s)
- Yui Ogawa
- Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
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32
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Suzuki T, Itoh T, Vantasin S, Minami S, Kutsuma Y, Ashida K, Kaneko TA, Morisawa Y, Miura T, Ozaki Y. Tip-enhanced Raman spectroscopic measurement of stress change in the local domain of epitaxial graphene on the carbon face of 4H-SiC(000–1). Phys Chem Chem Phys 2014; 16:20236-40. [DOI: 10.1039/c4cp02078b] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We measured TERS spectra of epitaxial graphene on the carbon face of 4H-SiC(000–1) and compared them with the corresponding normal Raman spectra.
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Affiliation(s)
- Toshiaki Suzuki
- Department of Chemistry
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
| | - Tamitake Itoh
- Nano-Bioanalysis Research Group
- Health Research Institute
- National Institute of Advanced Industrial Science and Technology (AIST)
- Takamatsu, Japan
| | - Sanpon Vantasin
- Department of Chemistry
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
| | - Satoshi Minami
- Department of Chemistry
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
| | - Yasunori Kutsuma
- Department of Physics
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
| | - Koji Ashida
- Department of Physics
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
| | - Tada-aki Kaneko
- Department of Physics
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
| | - Yusuke Morisawa
- Department of Chemistry
- School of Science and Engineering
- Kinki University
- Higashi-Osaka, Japan
| | | | - Yukihiro Ozaki
- Department of Chemistry
- School of Science and Technology
- Kwansei Gakuin University
- Sanda, Japan
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33
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Wang Q, Li Y, Bai B, Mao W, Wang Z, Ren N. Effects of silicon dioxide surface roughness on Raman characteristics and mechanical properties of graphene. RSC Adv 2014. [DOI: 10.1039/c4ra08369e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The effects of the surface roughness of a silicon dioxide substrate on the mechanical properties and Raman scattering of graphene prepared by chemical vapor deposition were investigated.
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Affiliation(s)
- Quan Wang
- School of Mechanical Engineering
- Jiangsu University
- Zhenjiang 212013, P. R. China
- State Key Laboratory of Transducer Technology
- Chinese Academy of Sciences
| | - Yun Li
- School of Mechanical Engineering
- Jiangsu University
- Zhenjiang 212013, P. R. China
| | - Bing Bai
- School of Mechanical Engineering
- Jiangsu University
- Zhenjiang 212013, P. R. China
| | - Wei Mao
- School of Mechanical Engineering
- Jiangsu University
- Zhenjiang 212013, P. R. China
| | - Zegao Wang
- State Key Laboratory of Electronic Thin Films and Integrated Devices
- University of Electronic Science and Technology of China
- Chengdu 610054, P. R. China
| | - Naifei Ren
- School of Mechanical Engineering
- Jiangsu University
- Zhenjiang 212013, P. R. China
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34
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Bissett MA, Tsuji M, Ago H. Strain engineering the properties of graphene and other two-dimensional crystals. Phys Chem Chem Phys 2014; 16:11124-38. [DOI: 10.1039/c3cp55443k] [Citation(s) in RCA: 175] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
This perspective discusses recent advances in using strain to engineer the properties of thin-layer materials such as graphene and transition metal dichalcogenides (TMDs).
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Affiliation(s)
- Mark A. Bissett
- Institute for Materials Chemistry and Engineering
- Kyushu University
- Fukuoka, Japan
| | - Masaharu Tsuji
- Institute for Materials Chemistry and Engineering
- Kyushu University
- Fukuoka, Japan
| | - Hiroki Ago
- Institute for Materials Chemistry and Engineering
- Kyushu University
- Fukuoka, Japan
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Bissett MA, Konabe S, Okada S, Tsuji M, Ago H. Enhanced chemical reactivity of graphene induced by mechanical strain. ACS NANO 2013; 7:10335-10343. [PMID: 24131427 DOI: 10.1021/nn404746h] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Control over chemical reactivity is essential in the field of nanotechnology. Graphene is a two-dimensional atomic sheet of sp(2) hybridized carbon with exceptional properties that can be altered by chemical functionalization. Here, we transferred single-layer graphene onto a flexible substrate and investigated the functionalization using different aryl diazonium molecules while applying mechanical strain. We found that mechanical strain can alter the structure of graphene, and dramatically increase the reaction rate, by a factor of up to 10, as well as increase the final degree of functionalization. Furthermore, we demonstrate that mechanical strain enables functionalization of graphene for both p- and n-type dopants, where unstrained graphene showed negligible reactivity. Theoretical calculations were also performed to support the experimental findings. Our findings offer a simple approach to control the chemical reactivity of graphene through the application of mechanical strain, allowing for a tuning of the properties of graphene.
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Affiliation(s)
- Mark A Bissett
- Institute for Materials Chemistry and Engineering, Kyushu University , Fukuoka 816-8580, Japan
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36
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On the growth mode of two-lobed curvilinear graphene domains at atmospheric pressure. Sci Rep 2013; 3:2571. [PMID: 23999168 PMCID: PMC3759841 DOI: 10.1038/srep02571] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 07/24/2013] [Indexed: 11/08/2022] Open
Abstract
We demonstrate the chemical vapor deposition (CVD) growth of 2-lobed symmetrical curvilinear graphene domains specifically on Cu{100} surface orientations at atmospheric pressure. We utilize electron backscattered diffraction, scanning electron microscopy and Raman spectroscopy to determine an as-yet unexplored growth mode producing such a shape and demonstrate how its growth and morphology are dependent on the underlying Cu crystal structure especially in the high CH4:H2 regime. We show that both monolayer and bilayer curvilinear domains are grown on Cu{100} surfaces; furthermore, we show that characteristic atmospheric pressure CVD hexagonal domains are grown on all other Cu facets with an isotropic growth rate which is more rapid than that on Cu{100}. These findings indicate that the Cu-graphene complex is predominant mechanistically at atmospheric pressure, which is an important step towards tailoring graphene properties via substrate engineering.
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37
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Lim CHYX, Sorkin A, Bao Q, Li A, Zhang K, Nesladek M, Loh KP. A hydrothermal anvil made of graphene nanobubbles on diamond. Nat Commun 2013; 4:1556. [PMID: 23462999 DOI: 10.1038/ncomms2579] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 02/07/2013] [Indexed: 12/25/2022] Open
Abstract
The hardness and virtual incompressibility of diamond allow it to be used in high-pressure anvil cell. Here we report a new way to generate static pressure by encapsulating single-crystal diamond with graphene membrane, the latter is well known for its superior nano-indentation strength and in-plane rigidity. Heating the diamond-graphene interface to the reconstruction temperature of diamond (~1,275 K) produces a high density of graphene nanobubbles that can trap water. At high temperature, chemical bonding between graphene and diamond is robust enough to allow the hybrid interface to act as a hydrothermal anvil cell due to the impermeability of graphene. Superheated water trapped within the pressurized graphene nanobubbles is observed to etch the diamond surface to produce a high density of square-shaped voids. The molecular structure of superheated water trapped in the bubble is probed using vibrational spectroscopy and dynamic changes in the hydrogen-bonding environment are observed.
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Affiliation(s)
- Candy Haley Yi Xuan Lim
- Department of Chemistry, Graphene Research Centre, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
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38
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Koyama T, Ito Y, Yoshida K, Tsuji M, Ago H, Kishida H, Nakamura A. Near-Infrared photoluminescence in the femtosecond time region in monolayer graphene on SiO₂. ACS NANO 2013; 7:2335-2343. [PMID: 23461396 DOI: 10.1021/nn305558r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We investigate the dynamical properties of photoexcited carriers in a single monolayer of graphene at room temperature in air using femtosecond time-resolved luminescence spectroscopy. The luminescence kinetics are observed in the near-infrared region of 0.7-1.4 eV and analyzed based on the two-temperature model describing the cooling of thermalized carriers via the carrier-optical phonon interaction. The observed luminescence in the range 0.7-0.9 eV is well reproduced by the model. In the range 1.0-1.4 eV, however, the luminescence, which decays in ∼300 fs, cannot be reproduced by this model. These results indicate that the carrier system is not completely thermalized in ∼300 fs. We also show the importance of the carrier-doping effect induced by the substrate and surrounding environment in the carrier cooling dynamics and the predominance of optical phonons over acoustic phonons in the carrier-phonon interactions even at a temperature of ∼400 K.
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Affiliation(s)
- Takeshi Koyama
- Department of Applied Physics, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan.
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