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Yu J, Han Y, Wang L, Xu F, Zhang H, Yu Y, Wu Q, Hu J. Visualizing Nonlinear Phononics in Layered ReSe 2. J Phys Chem Lett 2021; 12:5178-5184. [PMID: 34037407 DOI: 10.1021/acs.jpclett.1c01172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nonlinear phononics has recently been demonstrated as a viable approach for dynamically modifying materials' properties. Conventionally, nonlinearity in the lattice dynamics is introduced via the "ionic" Raman scattering, in which infrared-active phonons (i.e., coherent ionic vibrations) serve as the intermediate state for transferring energy to Raman-active phonons. Here we report that it is also possible to achieve phononic nonlinearity through the "electronic" route, a process that relies on excited electronic states to initiate energy exchange among Raman-active phonons. Taking layered ReSe2 as a model system, we use coherent phonon spectroscopy with a pump energy larger than the band gap to follow lattice dynamics and observe the nonlinear coupling between both Raman-active intralayer atomic oscillations and interlayer breathing modes. In addition, we show that such nonlinear phononic coupling is highly dependent on the environment temperature. This work, which demonstrates a different and novel mechanism, may enrich the toolkit for controlling material properties by means of nonlinear phononics.
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Affiliation(s)
- Junhong Yu
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Yadong Han
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
- State Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang, 621010, China
| | - Longyu Wang
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Fang Xu
- State Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang, 621010, China
| | - Hang Zhang
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
- State Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang, 621010, China
| | - Yuying Yu
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Qiang Wu
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Jianbo Hu
- Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, 621900, China
- State Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang, 621010, China
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Du X, Lee Y, Zhang Y, Yu T, Kim K, Liu N. Electronically Weak Coupled Bilayer MoS 2 at Various Twist Angles via Folding. ACS APPLIED MATERIALS & INTERFACES 2021; 13:22819-22827. [PMID: 33945252 DOI: 10.1021/acsami.1c03135] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Constructing a bilayer system with defined twist angles is an effective way to engineer the physical properties of two-dimensional (2D) materials, opening up a new research area of twistronics. How to achieve high-quality bilayer 2D materials in a controlled and mass production way is of primary importance to this emerging area. In this work, we present a strategy for the large-scale fabrication of twisted bilayer molybdenum disulfide (MoS2) through photolithography patterning and folding of single-crystal monolayer MoS2. Atomic resolution transmission electron spectroscopy directly confirms that the as-achieved folded bilayer MoS2 is of high quality with targeted twist angles. Various twist angles result in tuning Raman mode frequencies and direct optical transition energies. Due to the weak interlayer coupling between the twisted layers, folded bilayers exhibit an extremely high photoluminescence with doubled intensity as compared to the unfolded monolayer, indicating a possible application in optoelectronic devices. Our work provides a new strategy to tailor the properties of MoS2, which will be beneficial to twistable electronics.
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Affiliation(s)
- Xiaojia Du
- Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Yangjin Lee
- Department of Physics, Yonsei University, Seoul 03722, Korea
| | - Yan Zhang
- Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Tianhao Yu
- Beijing Graphene Institute, Beijing 100095, P. R. China
| | - Kwanpyo Kim
- Department of Physics, Yonsei University, Seoul 03722, Korea
| | - Nan Liu
- Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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Thermal expansion coefficient of few-layer MoS 2 studied by temperature-dependent Raman spectroscopy. Sci Rep 2021; 11:7037. [PMID: 33782514 PMCID: PMC8007611 DOI: 10.1038/s41598-021-86479-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 03/04/2021] [Indexed: 02/01/2023] Open
Abstract
The thermal expansion coefficient is an important thermal parameter that influences the performance of nanodevices based on two-dimensional materials. To obtain the thermal expansion coefficient of few-layer MoS2, suspended MoS2 and supported MoS2 were systematically investigated using Raman spectroscopy in the temperature range from 77 to 557 K. The temperature-dependent evolution of the Raman frequency shift for suspended MoS2 exhibited prominent differences from that for supported MoS2, obviously demonstrating the effect due to the thermal expansion coefficient mismatch between MoS2 and the substrate. The intrinsic thermal expansion coefficients of MoS2 with different numbers of layers were calculated. Interestingly, negative thermal expansion coefficients were obtained below 175 K, which was attributed to the bending vibrations in the MoS2 layer during cooling. Our results demonstrate that Raman spectroscopy is a feasible tool for investigating the thermal properties of few-layer MoS2 and will provide useful information for its further application in photoelectronic devices.
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Cheon Y, Lim SY, Kim K, Cheong H. Structural Phase Transition and Interlayer Coupling in Few-Layer 1T' and T d MoTe 2. ACS NANO 2021; 15:2962-2970. [PMID: 33480685 DOI: 10.1021/acsnano.0c09162] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We performed polarized Raman spectroscopy on mechanically exfoliated few-layer MoTe2 samples and observed both 1T' and Td phases at room temperature. Few-layer 1T' and Td MoTe2 exhibited a significant difference especially in interlayer vibration modes, from which the interlayer coupling strengths were extracted using the linear chain model: strong in-plane anisotropy was observed in both phases. Furthermore, temperature-dependent Raman measurements revealed a peculiar phase transition behavior in few-layer 1T' MoTe2. In contrast to bulk 1T' MoTe2 crystals, where the phase transition to the Td phase occurs at ∼250 K, the temperature-driven phase transition to the Td phase is increasingly suppressed as the thickness is reduced, and the transition and the critical temperature varied dramatically from sample to sample even for the same thickness. Raman spectra of intermediate phases that correspond to neither 1T' nor Td phase with different interlayer vibration modes were observed, which suggests that several metastable phases exist with similar total energies.
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Affiliation(s)
- Yeryun Cheon
- Department of Physics, Sogang University, Seoul 04107, Korea
| | - Soo Yeon Lim
- Department of Physics, Sogang University, Seoul 04107, Korea
| | - Kangwon Kim
- Department of Physics, Sogang University, Seoul 04107, Korea
| | - Hyeonsik Cheong
- Department of Physics, Sogang University, Seoul 04107, Korea
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Abstract
Rhenium disulfide (ReS2), known in nature as the mineral rheniite, is a very interesting compound owing to its remarkable fundamental properties and great potential to develop novel device applications. Here we perform density functional theory (DFT) calculations to investigate the structural properties and compression behavior of this compound and also of the (Re,Mo)S2 solid solution as a function of Re/Mo content. Our theoretical analysis is complemented with high-pressure X-ray diffraction (XRD) measurements, which have allowed us to reevaluate the phase transition pressure and equation of state of 1T-ReS2. We have observed the 1T-to-1T’ phase transition at pressures as low as ~2 GPa, and we have obtained an experimental bulk modulus, B0, equal to 46(2) GPa. This value is in good agreement with PBE+D3 calculations, thus confirming the ability of this functional to model the compression behavior of layered transition metal dichalcogenides, provided that van der Waals corrections are taken into account. Our experimental data and analysis confirm the important role played by van der Waals effects in the high-pressure properties of 1T-ReS2.
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Ong ZY, Cai Y, Zhang G, Zhang YW. Theoretical analysis of thermal boundary conductance of MoS 2-SiO 2 and WS 2-SiO 2 interface. NANOTECHNOLOGY 2021; 32:135402. [PMID: 33410419 DOI: 10.1088/1361-6528/abd208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Understanding the physical processes involved in interfacial heat transfer is critical for the interpretation of thermometric measurements and the optimization of heat dissipation in nanoelectronic devices that are based on transition metal dichalcogenide (TMD) semiconductors. We model the phononic and electronic contributions to the thermal boundary conductance (TBC) variability for the MoS2-SiO2 and WS2-SiO2 interface. A phenomenological theory to model diffuse phonon transport at disordered interfaces is introduced and yields G = 13.5 and 12.4 MW K-1 m-2 at 300 K for the MoS2-SiO2 and WS2-SiO2 interface, respectively. We compare its predictions to those of the coherent phonon model and find that the former fits the MoS2-SiO2 data from experiments and simulations significantly better. Our analysis suggests that heat dissipation at the TMD-SiO2 interface is dominated by phonons scattered diffusely by the rough interface although the electronic TBC contribution can be significant even at low electron densities (n ≤ 1012 cm-2) and may explain some of the variation in the experimental TBC data from the literature. The physical insights from our study can be useful for the development of thermally aware designs in TMD-based nanoelectronics.
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Affiliation(s)
- Zhun-Yong Ong
- Institute of High Performance Computing, A*STAR, Singapore 138632, Singapore
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57
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Vialla F, Del Fatti N. Time-Domain Investigations of Coherent Phonons in van der Waals Thin Films. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E2543. [PMID: 33348750 PMCID: PMC7766349 DOI: 10.3390/nano10122543] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/11/2020] [Accepted: 12/14/2020] [Indexed: 01/31/2023]
Abstract
Coherent phonons can be launched in materials upon localized pulsed optical excitation, and be subsequently followed in time-domain, with a sub-picosecond resolution, using a time-delayed pulsed probe. This technique yields characterization of mechanical, optical, and electronic properties at the nanoscale, and is taken advantage of for investigations in material science, physics, chemistry, and biology. Here we review the use of this experimental method applied to the emerging field of homo- and heterostructures of van der Waals materials. Their unique structure corresponding to non-covalently stacked atomically thin layers allows for the study of original structural configurations, down to one-atom-thin films free of interface defect. The generation and relaxation of coherent optical phonons, as well as propagative and resonant breathing acoustic phonons, are comprehensively discussed. This approach opens new avenues for the in situ characterization of these novel materials, the observation and modulation of exotic phenomena, and advances in the field of acoustics microscopy.
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Affiliation(s)
- Fabien Vialla
- Institut Lumière Matière UMR 5306, Université Claude Bernard Lyon 1, CNRS, Université de Lyon, F-69622 Villeurbanne, France;
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58
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Li X, Chen C, Yang Y, Lei Z, Xu H. 2D Re-Based Transition Metal Chalcogenides: Progress, Challenges, and Opportunities. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2002320. [PMID: 33304762 PMCID: PMC7709994 DOI: 10.1002/advs.202002320] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/22/2020] [Indexed: 05/16/2023]
Abstract
The rise of 2D transition-metal dichalcogenides (TMDs) materials has enormous implications for the scientific community and beyond. Among TMDs, ReX2 (X = S, Se) has attracted significant interest regarding its unusual 1T' structure and extraordinary properties in various fields during the past 7 years. For instance, ReX2 possesses large bandgaps (ReSe2: 1.3 eV, ReS2: 1.6 eV), distinctive interlayer decoupling, and strong anisotropic properties, which endow more degree of freedom for constructing novel optoelectronic, logic circuit, and sensor devices. Moreover, facile ion intercalation, abundant active sites, together with stable 1T' structure enable them great perspective to fabricate high-performance catalysts and advanced energy storage devices. In this review, the structural features, fundamental physicochemical properties, as well as all existing applications of Re-based TMDs materials are comprehensively introduced. Especially, the emerging synthesis strategies are critically analyzed and pay particular attention is paid to its growth mechanism with probing the assembly process of domain architectures. Finally, current challenges and future opportunities regarding the controlled preparation methods, property, and application exploration of Re-based TMDs are discussed.
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Affiliation(s)
- Xiaobo Li
- Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationShaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an710119P. R. China
| | - Chao Chen
- Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationShaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an710119P. R. China
| | - Yang Yang
- Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationShaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an710119P. R. China
| | - Zhibin Lei
- Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationShaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an710119P. R. China
| | - Hua Xu
- Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationShaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an710119P. R. China
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59
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Wang L, Jiang SL, Zhang Q, Luo Y. Multi-domain high-resolution platform for integrated spectroscopy and microscopy characterizations. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp2006093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Li Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Shen-long Jiang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Qun Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yi Luo
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
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60
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Arcudia J, Kempt R, Cifuentes-Quintal ME, Heine T, Merino G. Blue Phosphorene Bilayer Is a Two-Dimensional Metal and an Unambiguous Classification Scheme for Buckled Hexagonal Bilayers. PHYSICAL REVIEW LETTERS 2020; 125:196401. [PMID: 33216566 DOI: 10.1103/physrevlett.125.196401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 09/10/2020] [Indexed: 06/11/2023]
Abstract
High-level first-principles computations predict blue phosphorene bilayer to be a two-dimensional metal. This structure has not been considered before and was identified by employing a block-diagram scheme that yields the complete set of five high-symmetry stacking configurations of buckled honeycomb layers, and allows their unambiguous classification. We show that all of these stacking configurations are stable or at least metastable both for blue phosphorene and gray arsenene bilayers. For blue phosphorene, the most stable stacking arrangement has not yet been reported, and surprisingly it is metallic, while the others are indirect band gap semiconductors. As it is impossible to interchange the stacking configurations by translations, all of them should be experimentally accessible via the transfer of monolayers. The metallic character of blue phosphorene bilayer is caused by its short interlayer distance of 3.01 Å and offers the exceptional possibility to design single elemental all-phosphorus transistors.
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Affiliation(s)
- Jessica Arcudia
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados, Unidad Mérida, 97310, Mérida, Yucatán, México
| | - Roman Kempt
- Technische Universität Dresden, Fakultät für Chemie und Lebensmittelchemie, Bergstraße 66c, 01062 Dresden, Germany
| | | | - Thomas Heine
- Technische Universität Dresden, Fakultät für Chemie und Lebensmittelchemie, Bergstraße 66c, 01062 Dresden, Germany
- Helmholtz Zentrum Dresden-Rossendorf, Leipzig Research Branch, Permoserstr. 15, 04318 Leipzig, Germany
- Department of Chemistry, Yonsei University, Seodaemun-gu, Seoul 120-749, Republic of Korea
| | - Gabriel Merino
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados, Unidad Mérida, 97310, Mérida, Yucatán, México
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61
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Giuffredi G, Mezzetti A, Perego A, Mazzolini P, Prato M, Fumagalli F, Lin YC, Liu C, Ivanov IN, Belianinov A, Colombo M, Divitini G, Ducati C, Duscher G, Puretzky AA, Geohegan DB, Di Fonzo F. Non-Equilibrium Synthesis of Highly Active Nanostructured, Oxygen-Incorporated Amorphous Molybdenum Sulfide HER Electrocatalyst. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2004047. [PMID: 33090682 DOI: 10.1002/smll.202004047] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 08/08/2020] [Indexed: 06/11/2023]
Abstract
Molybdenum sulfide emerged as promising hydrogen evolution reaction (HER) electrocatalyst thanks to its high intrinsic activity, however its limited active sites exposure and low conductivity hamper its performance. To address these drawbacks, the non-equilibrium nature of pulsed laser deposition (PLD) is exploited to synthesize self-supported hierarchical nanoarchitectures by gas phase nucleation and sequential attachment of defective molybdenum sulfide clusters. The physics of the process are studied by in situ diagnostics and correlated to the properties of the resulting electrocatalyst. The as-synthesized architectures have a disordered nanocrystalline structure, with nanodomains of bent, defective S-Mo-S layers embedded in an amorphous matrix, with excess sulfur and segregated molybdenum particles. Oxygen incorporation in this structure fosters the creation of amorphous oxide/oxysulfide nanophases with high electrical conductivity, enabling fast electron transfer to the active sites. The combined effect of the nanocrystalline pristine structure and the surface oxidation enhances the performance leading to small overpotentials, very fast kinetics (35.1 mV dec-1 Tafel slope) and remarkable long-term stability for continuous operation up to -1 A cm-2. This work shows possible new avenues in catalytic design arising from a non-equilibrium technique as PLD and the importance of structural and chemical control to improve the HER performance of MoS-based catalysts.
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Affiliation(s)
- Giorgio Giuffredi
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
- Department of Energy, Politecnico di Milano, Via Lambruschini 4, Milano, 20156, Italy
| | - Alessandro Mezzetti
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
| | - Andrea Perego
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
- Department of Energy, Politecnico di Milano, Via Lambruschini 4, Milano, 20156, Italy
| | - Piero Mazzolini
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
| | - Mirko Prato
- Materials Characterization Facility, Istituto Italiano di Tecnologia, Via Morego 30, Genova, 16163, Italy
| | - Francesco Fumagalli
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
| | - Yu-Chuan Lin
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Chenze Liu
- Department of Material Science and Engineering, University of Tennessee, Knoxville, TN, 37996, USA
| | - Ilia N Ivanov
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Alex Belianinov
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Massimo Colombo
- Nanochemistry Department, Istituto Italiano di Tecnologia, Via Morego 30, Genova, 16130, Italy
| | - Giorgio Divitini
- Department of Materials Science & Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
| | - Caterina Ducati
- Department of Materials Science & Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
| | - Gerd Duscher
- Department of Material Science and Engineering, University of Tennessee, Knoxville, TN, 37996, USA
| | - Alexander A Puretzky
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - David B Geohegan
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Fabio Di Fonzo
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
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Debnath R, Maity I, Biswas R, Raghunathan V, Jain M, Ghosh A. Evolution of high-frequency Raman modes and their doping dependence in twisted bilayer MoS 2. NANOSCALE 2020; 12:17272-17280. [PMID: 32400768 DOI: 10.1039/c9nr09897f] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Twisted van der Waals heterostructures provide a new platform for studying strongly correlated quantum phases. The interlayer coupling in these heterostructures is sensitive to the twist angle (θ) and key to controllably tuning several interesting properties. Here, we demonstrate the systematic evolution of the interlayer coupling strength with twist angle in bilayer MoS2 using a combination of Raman spectroscopy and classical simulations. At zero doping, we observe a monotonic increase in the separation between the A1g and E2g1 mode frequencies as θ decreases from 10°→ 1°, and the separation approaches that of a bilayer at small twist angles. Furthermore, using doping dependent Raman spectroscopy, we reveal the θ dependent softening and broadening of the A1g mode, whereas the E2g1 mode remains unaffected. Using first principles based simulations, we demonstrate large (weak) electron-phonon coupling for the A1g (E2g1) mode, which explains the experimentally observed trends. Our study provides a non-destructive way to characterize the twist angle and the interlayer coupling and establishes the manipulation of phonons in twisted bilayer MoS2 (twistnonics).
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Affiliation(s)
- Rahul Debnath
- Department of Physics, Indian Institute of Science, Bangalore 560012, India.
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63
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Taghizadeh A, Leffers U, Pedersen TG, Thygesen KS. A library of ab initio Raman spectra for automated identification of 2D materials. Nat Commun 2020; 11:3011. [PMID: 32541789 PMCID: PMC7296020 DOI: 10.1038/s41467-020-16529-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 05/06/2020] [Indexed: 11/09/2022] Open
Abstract
Raman spectroscopy is frequently used to identify composition, structure and layer thickness of 2D materials. Here, we describe an efficient first-principles workflow for calculating resonant first-order Raman spectra of solids within third-order perturbation theory employing a localized atomic orbital basis set. The method is used to obtain the Raman spectra of 733 different monolayers selected from the Computational 2D Materials Database (C2DB). We benchmark the computational scheme against available experimental data for 15 known monolayers. Furthermore, we propose an automatic procedure for identifying a material based on an input experimental Raman spectrum and apply it to the cases of MoS2 (H-phase) and WTe2 (T[Formula: see text]-phase). The Raman spectra of all materials at different excitation frequencies and polarization configurations are freely available from the C2DB. Our comprehensive and easily accessible library of ab initio Raman spectra should be valuable for both theoreticians and experimentalists in the field of 2D materials.
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Affiliation(s)
- Alireza Taghizadeh
- Department of Materials and Production, Aalborg University, Aalborg, Øst, 9220, Denmark.
- Center for Nanostructured Graphene (CNG), Aalborg, Øst, 9220, Denmark.
- Computational Atomic-scale Materials Design (CAMD), Department of Physics, Technical University of Denmark (DTU), Lyngby, 2800 Kgs, Denmark.
| | - Ulrik Leffers
- Computational Atomic-scale Materials Design (CAMD), Department of Physics, Technical University of Denmark (DTU), Lyngby, 2800 Kgs, Denmark
| | - Thomas G Pedersen
- Department of Materials and Production, Aalborg University, Aalborg, Øst, 9220, Denmark
- Center for Nanostructured Graphene (CNG), Aalborg, Øst, 9220, Denmark
| | - Kristian S Thygesen
- Computational Atomic-scale Materials Design (CAMD), Department of Physics, Technical University of Denmark (DTU), Lyngby, 2800 Kgs, Denmark
- Center for Nanostructured Graphene (CNG), Technical University of Denmark (DTU), Lyngby, 2800 Kgs, Denmark
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64
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Lim SY, Lee JU, Kim JH, Liang L, Kong X, Nguyen TTH, Lee Z, Cho S, Cheong H. Polytypism in few-layer gallium selenide. NANOSCALE 2020; 12:8563-8573. [PMID: 32248214 DOI: 10.1039/d0nr00165a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Gallium selenide (GaSe) is one of the layered group-III metal monochalcogenides, which has an indirect bandgap in the monolayer and a direct bandgap in bulk unlike other conventional transition metal dichalcogenides (TMDs) such as MoX2 and WX2 (X = S and Se). Four polytypes of bulk GaSe, designated as β-, ε-, γ-, and δ-GaSe, have been reported. Since different polytypes result in different optical and electrical properties even with the same thickness, identifying the polytype is essential in utilizing this material for various optoelectronic applications. We performed polarized Raman measurements on GaSe and found different ultra-low-frequency Raman spectra of inter-layer vibrational modes even with the same thickness due to different stacking sequences of the polytypes. By comparing the ultra-low-frequency Raman spectra with the theoretical calculations and high-resolution electron microscopy measurements, we established the correlation between the ultra-low-frequency Raman spectra and the stacking sequences of trilayer GaSe. We further found that the AB-type stacking is more stable than the AA'-type stacking in GaSe.
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Affiliation(s)
- Soo Yeon Lim
- Department of Physics, Sogang University, Seoul 04107, Korea.
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Nguyen GD, Oyedele AD, Haglund A, Ko W, Liang L, Puretzky AA, Mandrus D, Xiao K, Li AP. Atomically Precise PdSe 2 Pentagonal Nanoribbons. ACS NANO 2020; 14:1951-1957. [PMID: 32023412 DOI: 10.1021/acsnano.9b08390] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We report atomically precise pentagonal PdSe2 nanoribbons (PNRs) fabricated on a pristine PdSe2 substrate with a hybrid method of top-down and bottom-up processes. The PNRs form a uniform array of dimer structure with a width of 2.4 nm and length of more than 200 nm. In situ four-probe scanning tunneling microscopy (STM) reveals metallic behavior of PNRs with ballistic transport for at least 20 nm in length. Density functional theory calculations produce a semiconducting density of states of isolated PNRs and find that the band gap narrows and disappears quickly once considering coupling between PNR stacking layers or interaction with the PdSe2 substrate. The coupling of PNRs is further corroborated by Raman spectroscopy and field-effect transistor measurements. The facile method of fabricating atomically precise PNRs offers an air-stable functional material for dimensional control.
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Affiliation(s)
- Giang D Nguyen
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
- Stewart Blusson Quantum Matter Institute , University of British Columbia , Vancouver , British Columbia V6T 1Z4 , Canada
| | - Akinola D Oyedele
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
- Bredesen Center for Interdisciplinary Research and Graduate Education , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Amanda Haglund
- Bredesen Center for Interdisciplinary Research and Graduate Education , University of Tennessee , Knoxville , Tennessee 37996 , United States
- Department of Materials Science and Engineering , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Wonhee Ko
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Liangbo Liang
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Alexander A Puretzky
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - David Mandrus
- Department of Materials Science and Engineering , University of Tennessee , Knoxville , Tennessee 37996 , United States
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Kai Xiao
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
- Bredesen Center for Interdisciplinary Research and Graduate Education , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - An-Ping Li
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
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66
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Li Y, Sun Y, Na G, Saidi WA, Zhang L. Diverse electronic properties of 2D layered Se-containing materials composed of quasi-1D atomic chains. Phys Chem Chem Phys 2020; 22:2122-2129. [PMID: 31907508 DOI: 10.1039/c9cp05914h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The two-dimensional (2D) atomically thin layered materials have attracted significant attention for constructing next-generation integrated electronic and optoelectronic devices. A special class of 2D materials composed of quasi one-dimensional (1D) atomic chains that show intriguing properties are less studied. Here, two Se-containing 2D layered materials α-Se and Sb2Se3 that have quasi-1D atomic chains are investigated via first-principles electronic structure calculations. Results shows that the electronic properties of n-monolayers (n-MLs) stacked α-Se and Sb2Se3 exhibit distinct layer-dependence electronic properties. The band gap of 2D α-Se remarkably decreases with increasing thickness, whereas the band gap of 2D Sb2Se3 show negligible change with thickness. The evolution of lattice phonon frequencies with thickness also show similar distinction. The underpinnings of the diverse electronic properties are attributed to the different electronic coupling among the layers of α-Se and Sb2Se3 that results in different van der Waals interactions among chains/layers. Our study demonstrates the rich diversity in the properties of 2D layered materials composed of lower-dimensional structural motifs.
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Affiliation(s)
- Yawen Li
- Key Laboratory of Automobile Materials of MOE and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China.
| | - Yuanhui Sun
- Key Laboratory of Automobile Materials of MOE and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China.
| | - Guangren Na
- Key Laboratory of Automobile Materials of MOE and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China.
| | - Wissam A Saidi
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
| | - Lijun Zhang
- Key Laboratory of Automobile Materials of MOE and School of Materials Science and Engineering, Jilin University, Changchun, 130012, China.
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67
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McCreary A, Simpson JR, Mai TT, McMichael RD, Douglas JE, Butch N, Dennis C, Aguilar RV, Walker ARH. Quasi-Two-Dimensional Magnon Identification in Antiferromagnetic FePS 3via Magneto-Raman Spectroscopy. PHYSICAL REVIEW. B 2020; 101:10.1103/PhysRevB.101.064416. [PMID: 38616972 PMCID: PMC11015466 DOI: 10.1103/physrevb.101.064416] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Recently it was discovered that van der Waals-bonded magnetic materials retain long range magnetic ordering down to a single layer, opening many avenues in fundamental physics and potential applications of these fascinating materials. One such material is FePS3, a large spin (S=2) Mott insulator where the Fe atoms form a honeycomb lattice. In the bulk, FePS3 has been shown to be a quasi-two-dimensional-Ising antiferromagnet, with additional features in the Raman spectra emerging below the Néel temperature (T N ) of approximately 120 K. Using magneto-Raman spectroscopy as an optical probe of magnetic structure, we show that one of these Raman-active modes in the magnetically ordered state is actually a magnon with a frequency of ≈3.7 THz (122 cm-1). Contrary to previous work, which interpreted this feature as a phonon, our Raman data shows the expected frequency shifting and splitting of the magnon as a function of temperature and magnetic field, respectively, where we determine the g-factor to be ≈2. In addition, the symmetry behavior of the magnon is studied by polarization-dependent Raman spectroscopy and explained using the magnetic point group of FePS3.
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Affiliation(s)
- Amber McCreary
- Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Jeffrey R. Simpson
- Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
- Department of Physics, Astronomy, and Geosciences, Towson University, Towson, MD 21252, USA
| | - Thuc T. Mai
- Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Robert D. McMichael
- Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Jason E. Douglas
- Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Nicholas Butch
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Cindi Dennis
- Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | | | - Angela R. Hight Walker
- Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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68
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Trusova EA, Titov DD, Kirichenko AN, Zorin MY. Effect of graphene sheet incorporation on the physicochemical properties of nano-alumina. NEW J CHEM 2020. [DOI: 10.1039/c9nj06317j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The colloidal processing method was suggested for obtaining chemically homogeneous composite powder based on graphene and nano-alumina.
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Affiliation(s)
- Elena A. Trusova
- Baikov Institute of Metallurgy and Materials Science
- RAS
- Moscow 119334
- Russia
| | - Dmitriy D. Titov
- Baikov Institute of Metallurgy and Materials Science
- RAS
- Moscow 119334
- Russia
| | - Alexey N. Kirichenko
- Technological Institute for Superhard and Novel Carbon Materials
- Moscow 142190
- Russia
| | - Michael Y. Zorin
- Baikov Institute of Metallurgy and Materials Science
- RAS
- Moscow 119334
- Russia
- D. Mendeleev University of Chemical Technology of Russia
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69
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Fang L, Liang W, Feng Q, Luo SN. Structural engineering of bilayer PtSe 2 thin films: a first-principles study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:455001. [PMID: 31341102 DOI: 10.1088/1361-648x/ab34bc] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
PtSe2 is an emerging layered two-dimensional material of applied interest. Its monolayer shows promising properties for applications in electronic devices, while the bandgap of a multilayer PtSe2 film can be tuned via changing its thickness. In this work the bilayer PtSe2 thin films are investigated as an example of structural engineering with first-principles calculations. Various van der Waals corrections schemes are firstly discussed, and the optB86b scheme shows a better description of the semiconductor-metal transition for PtSe2 films. Six bilayer PtSe2 thin films in different stacking modes are constructed in order to structurally tune the electronic and transport properties. The bandgap can be effectively broadened with the structural engineering for wider potential applications. The carrier mobility, dynamical stability and Raman spectra are also calculated and discussed.
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Affiliation(s)
- Limei Fang
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, and Institute of Materials Dynamics, Southwest Jiaotong University, Chengdu, Sichuan 610031, People's Republic of China
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70
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Peterson W, Hiramatsu K, Goda K. Sagnac-enhanced impulsive stimulated Raman scattering for highly sensitive low-frequency Raman spectroscopy. OPTICS LETTERS 2019; 44:5282-5285. [PMID: 31674988 DOI: 10.1364/ol.44.005282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
The "fingerprint" (500-1800 cm-1) and "high-frequency" (2400-4000 cm-1) regions in Raman spectroscopy are commonly used for label-free chemical analysis, while the "low-frequency" region (<200 cm-1) is often overlooked, despite containing rich information. This is largely due to the challenge of measuring weak Raman signals that are obscured by strong Rayleigh scattering. Here we propose and experimentally demonstrate Sagnac-enhanced impulsive stimulated Raman scattering (SE-ISRS), a filter-free method for time-domain Raman spectroscopy that overcomes the challenge and provides low-frequency Raman spectra at all probe frequencies. Using SE-ISRS for simultaneous low-frequency and fingerprint region measurements, we demonstrate a >5× enhancement of the signal-to-noise ratio compared to conventional ISRS spectroscopy.
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71
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Sun YJ, Tan QH, Liu XL, Gao YF, Zhang J. Probing the Magnetic Ordering of Antiferromagnetic MnPS 3 by Raman Spectroscopy. J Phys Chem Lett 2019; 10:3087-3093. [PMID: 31088058 DOI: 10.1021/acs.jpclett.9b00758] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Ferromagnetic/antiferromagnetic materials are of crucial importance in information storage and spintronics devices. Herein we present a comprehensive study of 2D Heisenberg-like antiferromagnetic material MnPS3 by optical contrast and Raman spectroscopy. We propose a criterion of 0.1 × ( N - 1) < (Δ R/ R)max < 0.1 × N ( N ≤ 7) to quickly identify the layer number N by using maximum optical contrast (Δ R/ R)max of few-layer MnPS3 on a SiO2/Si substrate (90 nm thick SiO2). The Raman modes are also identified by polarization Raman spectroscopy. Furthermore, by temperature-dependent Raman measurements, we obtain three phase transition temperatures of MnPS3. The transition temperature at around 80 K corresponds to the transition from the antiferromagnetic to paramagnetic phase; the one at around 120 K is related to its second magnetic phase transition temperature due to two-dimensional spin critical fluctuations; the one at around 55 K is associated with unbinding of spin vortices. Our studies provide more evidence to advance knowledge of the magnetic critical dynamics of 2D ferromagnetic/antiferromagnetic systems.
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Affiliation(s)
- Yu-Jia Sun
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- Center of Materials Science and Optoelectronics Engineering , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Qing-Hai Tan
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- Center of Materials Science and Optoelectronics Engineering , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Xue-Lu Liu
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
| | - Yuan-Fei Gao
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
| | - Jun Zhang
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- Center of Materials Science and Optoelectronics Engineering , University of Chinese Academy of Sciences , Beijing 100049 , China
- CAS Center of Excellence in Topological Quantum Computation , University of Chinese Academy of Sciences , Beijing 101408 , China
- Beijing Academy of Quantum Information Science , Beijing 100193 , China
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72
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Cross-dimensional electron-phonon coupling in van der Waals heterostructures. Nat Commun 2019; 10:2419. [PMID: 31160599 PMCID: PMC6546732 DOI: 10.1038/s41467-019-10400-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/08/2019] [Indexed: 11/12/2022] Open
Abstract
The electron-phonon coupling (EPC) in a material is at the frontier of the fundamental research, underlying many quantum behaviors. van der Waals heterostructures (vdWHs) provide an ideal platform to reveal the intrinsic interaction between their electrons and phonons. In particular, the flexible van der Waals stacking of different atomic crystals leads to multiple opportunities to engineer the interlayer phonon modes for EPC. Here, in hBN/WS2 vdWH, we report the strong cross-dimensional coupling between the layer-breathing phonons well extended over tens to hundreds of layer thick vdWH and the electrons localized within the few-layer WS2 constituent. The strength of such cross-dimensional EPC can be well reproduced by a microscopic picture through the mediation by the interfacial coupling and also the interlayer bond polarizability model in vdWHs. The study on cross-dimensional EPC paves the way to manipulate the interaction between electrons and phonons in various vdWHs by interfacial engineering for possible interesting physical phenomena. The strength of electron-phonon coupling can be directly probed by Raman spectroscopy. Here, the authors use low-frequency Raman spectroscopy to unveil the existence of a strong cross-dimensional coupling between the bulk-like layer-breathing phonons in an hBN/WS2 heterostructure and the electrons localized within its few-layer WS2 constituent.
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73
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Soubelet P, Reynoso AA, Fainstein A, Nogajewski K, Potemski M, Faugeras C, Bruchhausen AE. The lifetime of interlayer breathing modes of few-layer 2H-MoSe 2 membranes. NANOSCALE 2019; 11:10446-10453. [PMID: 31112191 DOI: 10.1039/c9nr02447f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
A time-resolved observation of coherent interlayer longitudinal acoustic phonons in thin layers of 2H-MoSe2 is reported. A femtosecond pump-probe technique is used to investigate the evolution of the energy loss of these vibrational modes in a wide selection of MoSe2 flakes with different thicknesses ranging from bilayer up to the bulk limit. By directly analysing the temporal decay of the modes, we can clearly distinguish an abrupt crossover related to the acoustic mean free path of the phonons in a layered system, and the constraints imposed on the acoustic decay channels when reducing the dimensionality. For thicker samples, the main acoustic attenuation mechanism is attributed to the scattering of the acoustic modes with thermal phonons. For samples thinner than ∼20 molecular layers, the predominant damping mechanism is ascribed to the effects of surface asperity. Losses intrinsic to the low dimensionality of single or few layer materials impose critical limitations for their use in optomechanical and optoelectronic devices.
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Affiliation(s)
- Pedro Soubelet
- Centro Atómico Bariloche & Instituto Balseiro (CNEA) and CONICET, 8400 S.C. de Bariloche, R.N., Argentina.
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74
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Liao CK, Phan J, Herrera M, Mahmoud MA. Modifying the Band Gap of Semiconducting Two-Dimensional Materials by Polymer Assembly into Different Structures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4956-4965. [PMID: 30874438 DOI: 10.1021/acs.langmuir.9b00205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Polyethylene glycol (PEG) assembled on the surface of two-dimensional tungsten disulfide (WS2) into a limited number of nanoislands (NIs), nanoshells (NSs), and granular nanoparticulates (GNPs) depending on its chain length. NI assemblies showed a nonmeasurable shift of photoluminescence (PL) and the A and B absorption peaks of WS2. This confirmed that the electronic doping by thiol is not effective. The PEG NS assembly displayed a smaller red shift of the PL and a slight decrease of the energy difference between the A and B absorption peaks of WS2. However, increasing the dielectric function on the surface of WS2 has a small influence on their optical properties. The PEG NP assembly on WS2 exhibited a significant red shift of the PL spectrum and a large decrease of the energy difference between A and B absorption peaks. Deforming the WS2 sheet by the PEG NP assembly decreased the orbital coupling and lowered the electronic direct band gap significantly. Raman bands of WS2 are shifted to a higher frequency on improving its mechanical strength after the PEG assembly.
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75
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Sun Y, Zhou Z, Huang Z, Wu J, Zhou L, Cheng Y, Liu J, Zhu C, Yu M, Yu P, Zhu W, Liu Y, Zhou J, Liu B, Xie H, Cao Y, Li H, Wang X, Liu K, Wang X, Wang J, Wang L, Huang W. Band Structure Engineering of Interfacial Semiconductors Based on Atomically Thin Lead Iodide Crystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1806562. [PMID: 30861234 DOI: 10.1002/adma.201806562] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/03/2019] [Indexed: 05/25/2023]
Abstract
To explore new constituents in two-dimensional (2D) materials and to combine their best in van der Waals heterostructures is in great demand as being a unique platform to discover new physical phenomena and to design novel functionalities in interface-based devices. Herein, PbI2 crystals as thin as a few layers are synthesized, particularly through a facile low-temperature solution approach with crystals of large size, regular shape, different thicknesses, and high yields. As a prototypical demonstration of band engineering of PbI2 -based interfacial semiconductors, PbI2 crystals are assembled with several transition metal dichalcogenide monolayers. The photoluminescence of MoS2 is enhanced in MoS2 /PbI2 stacks, while a dramatic photoluminescence quenching of WS2 and WSe2 is revealed in WS2 /PbI2 and WSe2 /PbI2 stacks. This is attributed to the effective heterojunction formation between PbI2 and these monolayers; type I band alignment in MoS2 /PbI2 stacks, where fast-transferred charge carriers accumulate in MoS2 with high emission efficiency, results in photoluminescence enhancement, and type II in WS2 /PbI2 and WSe2 /PbI2 stacks, with separated electrons and holes suitable for light harvesting, results in photoluminescence quenching. The results demonstrate that MoS2 , WS2 , and WSe2 monolayers with similar electronic structures show completely distinct light-matter interactions when interfacing with PbI2 , providing unprecedented capabilities to engineer the device performance of 2D heterostructures.
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Affiliation(s)
- Yan Sun
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Zishu Zhou
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Zhen Huang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Jiangbin Wu
- Ming Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA, 90089, USA
| | - Liujiang Zhou
- Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Yang Cheng
- State Key Laboratory for Mesoscopic Physics, School of Physics Department, Peking University, Beijing, 100871, China
| | - Jinqiu Liu
- National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing, 210093, China
| | - Chao Zhu
- Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Maotao Yu
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Peng Yu
- School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wei Zhu
- Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Yue Liu
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Jian Zhou
- National Laboratory of Solid-State Microstructures School of Electronic Science and Engineering Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Bowen Liu
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Hongguang Xie
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Yi Cao
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Hai Li
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Xinran Wang
- National Laboratory of Solid-State Microstructures School of Electronic Science and Engineering Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Kaihui Liu
- State Key Laboratory for Mesoscopic Physics, School of Physics Department, Peking University, Beijing, 100871, China
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing, 210093, China
| | - Jianpu Wang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Lin Wang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Wei Huang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, Shaanxi, China
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76
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Zhang X, Liao Q, Kang Z, Liu B, Ou Y, Du J, Xiao J, Gao L, Shan H, Luo Y, Fang Z, Wang P, Sun Z, Zhang Z, Zhang Y. Self-Healing Originated van der Waals Homojunctions with Strong Interlayer Coupling for High-Performance Photodiodes. ACS NANO 2019; 13:3280-3291. [PMID: 30803226 DOI: 10.1021/acsnano.8b09130] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The dangling-bond-free surfaces of van der Waals (vdW) materials make it possible to build ultrathin junctions. Fundamentally, the interfacial phenomena and related optoelectronic properties of vdW junctions are modulated by the interlayer coupling effect. However, the weak interlayer coupling of vdW heterostructures limits the interlayer charge transfer efficiency, resulting in low photoresponsivity. Here, a bilayer MoS2 homogeneous junction is constructed by stacking the as-grown onto the self-healed monolayer MoS2. The homojunction barrier of ∼165 meV is obtained by the electronic structure modulation of defect self-healing. This homojunction reveals the stronger interlayer coupling effect in comparison with vdW heterostructures. This ultrastrong interlayer coupling effect is experimentally verified by Raman spectra and angle-resolved photoemission spectroscopy. The ultrafast interlayer charge transfer takes place within ∼447 fs, which is faster than those of most vdW heterostructures. Furthermore, the homojunction photodiode manifests outstanding rectifying behavior with an ideal factor of ∼1.6, perfect air stability over 12 months, and high responsivity of ∼54.6 mA/W. Moreover, the interlayer exciton peak of ∼1.66 eV is found in vdW homojunctions. This work offers an uncommon vdW junction with strong interlayer coupling and perfects the relevance of interlayer coupling and interlayer charge transfer.
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Affiliation(s)
- Xiankun Zhang
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Qingliang Liao
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Zhuo Kang
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Baishan Liu
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Yang Ou
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Junli Du
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Jiankun Xiao
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Li Gao
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
| | - Hangyong Shan
- School of Physics, State Key Laboratory for Mesoscopic Physics, Collaborative Innovation Center of Quantum Matter , Peking University , Beijing 100871 , China
| | - Yang Luo
- School of Physics, State Key Laboratory for Mesoscopic Physics, Collaborative Innovation Center of Quantum Matter , Peking University , Beijing 100871 , China
| | - Zheyu Fang
- School of Physics, State Key Laboratory for Mesoscopic Physics, Collaborative Innovation Center of Quantum Matter , Peking University , Beijing 100871 , China
| | - Pengdong Wang
- National Synchrotron Radiation Laboratory , University of Science and Technology of China , Hefei , Anhui 230029 , China
| | - Zhe Sun
- National Synchrotron Radiation Laboratory , University of Science and Technology of China , Hefei , Anhui 230029 , China
| | - Zheng Zhang
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
- Beijing Municipal Key Laboratory for Advanced Energy Materials and Technologies , University of Science and Technology Beijing , Beijing 100083 , China
| | - Yue Zhang
- State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering , University of Science and Technology Beijing , Beijing 100083 , China
- Beijing Municipal Key Laboratory for Advanced Energy Materials and Technologies , University of Science and Technology Beijing , Beijing 100083 , China
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77
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Wu J, Xie L. Structural Quantification for Graphene and Related Two-Dimensional Materials by Raman Spectroscopy. Anal Chem 2018; 91:468-481. [DOI: 10.1021/acs.analchem.8b04991] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Juanxia Wu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
| | - Liming Xie
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- International College, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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78
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Lin ML, Tan QH, Wu JB, Chen XS, Wang JH, Pan YH, Zhang X, Cong X, Zhang J, Ji W, Hu PA, Liu KH, Tan PH. Moiré Phonons in Twisted Bilayer MoS 2. ACS NANO 2018; 12:8770-8780. [PMID: 30086224 DOI: 10.1021/acsnano.8b05006] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The material choice, layer thickness, and twist angle widely enrich the family of van der Waals heterostructures (vdWHs), providing multiple degrees of freedom to engineer their optical and electronic properties. The moiré patterns in vdWHs create a periodic potential for electrons and excitons to yield many interesting phenomena, such as Hofstadter butterfly spectrum and moiré excitons. Here, in the as-grown/transferred twisted bilayer MoS2 (tBLMs), one of the simplest prototypes of vdWHs, we show that the periodic potentials of moiré patterns also modify the properties of phonons of its monolayer MoS2 constituent to generate Raman modes related to moiré phonons. These Raman modes correspond to zone-center phonons in tBLMs, which are folded from the off-center phonons in monolayer MoS2. However, the folded phonons related to crystallographic superlattices are not observed in the Raman spectra. By varying the twist angle, the moiré phonons of tBLM can be exploited to map the phonon dispersions of the monolayer constituent. The lattice dynamics of the moiré phonons are modulated by the patterned interlayer coupling resulting from periodic potential of moiré patterns, as confirmed by density functional theory calculations. The Raman intensity related to moiré phonons in all tBLMs are strongly enhanced when the excitation energy approaches the C exciton energy. This study can be extended to various vdWHs to deeply understand their Raman spectra, moiré phonons, lattice dynamics, excitonic effects, and interlayer coupling.
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Affiliation(s)
- Miao-Ling Lin
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- CAS Center of Excellence in Topological Quantum Computation and College of Materials Science and Opto-Electronic Technology , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Qing-Hai Tan
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- CAS Center of Excellence in Topological Quantum Computation and College of Materials Science and Opto-Electronic Technology , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Jiang-Bin Wu
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
| | - Xiao-Shuang Chen
- School of Materials Science and Engineering, MOE Key Laboratory of Micro-Systems and Micro-Structures Manufacturing , Harbin Institute of Technology , Harbin 150080 , China
| | - Jin-Huan Wang
- State Key Laboratory of Mesoscopic Physics, School of Physics and Collaborative Innovation Center Quantum Matter , Peking University , Beijing 100871 , China
| | - Yu-Hao Pan
- Department of Physics , Renmin University of China , Beijing 100872 , China
| | - Xin Zhang
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
| | - Xin Cong
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- CAS Center of Excellence in Topological Quantum Computation and College of Materials Science and Opto-Electronic Technology , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Jun Zhang
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- CAS Center of Excellence in Topological Quantum Computation and College of Materials Science and Opto-Electronic Technology , University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Wei Ji
- Department of Physics , Renmin University of China , Beijing 100872 , China
| | - Ping-An Hu
- School of Materials Science and Engineering, MOE Key Laboratory of Micro-Systems and Micro-Structures Manufacturing , Harbin Institute of Technology , Harbin 150080 , China
| | - Kai-Hui Liu
- State Key Laboratory of Mesoscopic Physics, School of Physics and Collaborative Innovation Center Quantum Matter , Peking University , Beijing 100871 , China
| | - Ping-Heng Tan
- State Key Laboratory of Superlattices and Microstructures , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China
- CAS Center of Excellence in Topological Quantum Computation and College of Materials Science and Opto-Electronic Technology , University of Chinese Academy of Sciences , Beijing 100049 , China
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79
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Kandemir A, Sahin H. Bilayers of Janus WSSe: monitoring the stacking type via the vibrational spectrum. Phys Chem Chem Phys 2018; 20:17380-17386. [PMID: 29905346 DOI: 10.1039/c8cp02802h] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Motivated by the recent successful synthesis of Janus type single layers of transition metal dichalcogenides, we investigate the stability, vibrational and electronic properties of the Janus single layer structure of WSSe and its bilayers by means of density functional theory. The structural and vibrational analysis show that the Janus single layer of WSSe forms a dynamically stable structure in the 2H phase. Owing to its non-centrosymmetric structure, the Janus WSSe single layer has two in-plane (E) and two out-of-plane (A) Raman active phonon modes. The eigen-frequencies of the prominent Raman active modes are calculated to be 277 (A) and 322 (E) cm-1. Similar to single layer WS2 and WSe2, Janus WSSe is a direct band gap semiconductor that has two electronically different faces. In addition, the possible bilayer stacking orders of the Janus WSSe single layers are investigated. It is found that there are 3 stacking types of bilayer Janus WSSe and each stacking type has distinctive Raman characteristics in its vibrational spectrum. Our results show that thanks to the vibrational characteristics, which stem from the distinctive interlayer interactions at different sides, the stability and stacking types of the bilayer of WSSe Janus structure can be monitored.
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Affiliation(s)
- A Kandemir
- Department of Materials Science and Engineering, Izmir Institute of Technology, 35430, Izmir, Turkey.
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80
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Wu JB, Lin ML, Cong X, Liu HN, Tan PH. Raman spectroscopy of graphene-based materials and its applications in related devices. Chem Soc Rev 2018; 47:1822-1873. [PMID: 29368764 DOI: 10.1039/c6cs00915h] [Citation(s) in RCA: 535] [Impact Index Per Article: 89.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Graphene-based materials exhibit remarkable electronic, optical, and mechanical properties, which has resulted in both high scientific interest and huge potential for a variety of applications. Furthermore, the family of graphene-based materials is growing because of developments in preparation methods. Raman spectroscopy is a versatile tool to identify and characterize the chemical and physical properties of these materials, both at the laboratory and mass-production scale. This technique is so important that most of the papers published concerning these materials contain at least one Raman spectrum. Thus, here, we systematically review the developments in Raman spectroscopy of graphene-based materials from both fundamental research and practical (i.e., device applications) perspectives. We describe the essential Raman scattering processes of the entire first- and second-order modes in intrinsic graphene. Furthermore, the shear, layer-breathing, G and 2D modes of multilayer graphene with different stacking orders are discussed. Techniques to determine the number of graphene layers, to probe resonance Raman spectra of monolayer and multilayer graphenes and to obtain Raman images of graphene-based materials are also presented. The extensive capabilities of Raman spectroscopy for the investigation of the fundamental properties of graphene under external perturbations are described, which have also been extended to other graphene-based materials, such as graphene quantum dots, carbon dots, graphene oxide, nanoribbons, chemical vapor deposition-grown and SiC epitaxially grown graphene flakes, composites, and graphene-based van der Waals heterostructures. These fundamental properties have been used to probe the states, effects, and mechanisms of graphene materials present in the related heterostructures and devices. We hope that this review will be beneficial in all the aspects of graphene investigations, from basic research to material synthesis and device applications.
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Affiliation(s)
- Jiang-Bin Wu
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
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81
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Iwata K, Karashima M, Ikeda Y, Inoue M, Fukami T. Discrimination and quantification of sulfathiazole polytypes using low-frequency Raman spectroscopy. CrystEngComm 2018. [DOI: 10.1039/c8ce00081f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Low-frequency Raman spectroscopy has advantage to discriminate and quantify polymorphs where common 2D superstructures are piled up with different mode.
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Affiliation(s)
- Kentaro Iwata
- Analytical Development
- Pharmaceutical Sciences
- Takeda Pharmaceutical Company Limited
- Fujisawa
- Japan
| | - Masatoshi Karashima
- Analytical Development
- Pharmaceutical Sciences
- Takeda Pharmaceutical Company Limited
- Fujisawa
- Japan
| | - Yukihiro Ikeda
- Analytical Development
- Pharmaceutical Sciences
- Takeda Pharmaceutical Company Limited
- Fujisawa
- Japan
| | - Motoki Inoue
- Department of Molecular Pharmaceutics
- Meiji Pharmaceutical University
- Kiyose
- Japan
| | - Toshiro Fukami
- Department of Molecular Pharmaceutics
- Meiji Pharmaceutical University
- Kiyose
- Japan
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