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Zhang C, Huang H, Ni X, Zhou Y, Kang L, Jiang W, Chen H, Zhong J, Liu F. Band gap reduction in van der Waals layered 2D materials via a de-charge transfer mechanism. NANOSCALE 2018; 10:16759-16764. [PMID: 30156239 DOI: 10.1039/c8nr04660c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A thickness dependent band gap is commonly found in layered two-dimensional (2D) materials. Here, using a C3N bilayer as a prototypical model, we systematically investigated the evolution of a band gap from a single layer to a bilayer using first principles calculations and tight binding modeling. We show that in addition to the widely known effect of interlayer hopping, de-charge transfer also plays an important role in tuning the band gap. The de-charge transfer is defined with reference to the charge states of atoms in the single layer without stacking, which shifts the energy level and modifies the band gap. Together with band edge splitting induced by the interlayer hopping, the energy level shifting caused by the de-charge transfer determines the size of the band gap in bilayer C3N. Our finding, applicable to other 2D semiconductors, provides an alternative approach for realizing band gap engineering in 2D materials.
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Affiliation(s)
- Chunxiao Zhang
- Hunan Provincial Key Laboratory of Micro-Nano Energy Materials and Devices, Xiangtan University, Hunan 411105, People's Republic of China.
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52
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Liu Y, Liu C, Wang X, He L, Wan X, Xu Y, Shi Y, Zhang R, Wang F. Photoresponsivity of an all-semimetal heterostructure based on graphene and WTe 2. Sci Rep 2018; 8:12840. [PMID: 30150760 PMCID: PMC6110789 DOI: 10.1038/s41598-018-29717-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 06/28/2018] [Indexed: 01/29/2023] Open
Abstract
Heterostructures based on two-dimensional (2D) materials have sparked wide interests in both fundamental physics and applied devices. Recently, Dirac/Weyl semimetals are emerging as capable functional materials for optoelectronic devices. However, thus far the interfacial coupling of an all-semimetal 2D heterostructure has not been investigated, and its effects on optoelectronic properties remain less well understood. Here, a heterostructure comprising of all semi-metallic constituents, namely graphene and WTe2, is fabricated. Standard photocurrent measurements on a graphene/WTe2 phototransistor reveal a pronounced photocurrent enhancement (a photoresponsivity ~8.7 A/W under 650 nm laser illumination). Transport and photocurrent mapping suggest that both photovoltaic and photothermoelectric effects contribute to the enhanced photoresponse of the hybrid system. Our results help to enrich the understanding of new and emerging device concepts based on 2D layered materials.
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Affiliation(s)
- Yujie Liu
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Chuan Liu
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiaomu Wang
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Liang He
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiangang Wan
- School of Physics, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Yongbing Xu
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Yi Shi
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Rong Zhang
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Fengqiu Wang
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China. .,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
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53
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Teng F, Hu K, Ouyang W, Fang X. Photoelectric Detectors Based on Inorganic p-Type Semiconductor Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1706262. [PMID: 29888448 DOI: 10.1002/adma.201706262] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 01/18/2018] [Indexed: 05/03/2023]
Abstract
Photoelectric detectors are the central part of modern photodetection systems with numerous commercial and scientific applications. p-Type semiconductor materials play important roles in optoelectronic devices. Photodetectors based on p-type semiconductor materials have attracted a great deal of attention in recent years because of their unique properties. Here, a comprehensive summary of the recent progress mainly on photodetectors based on inorganic p-type semiconductor materials is presented. Various structures, including photoconductors, phototransistors, homojunctions, heterojunctions, p-i-n junctions, and metal-semiconductor junctions of photodetectors based on inorganic p-type semiconductor materials, are discussed and summarized. Perspectives and an outlook, highlighting the promising future directions of this research field, are also given.
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Affiliation(s)
- Feng Teng
- Department of Materials Science, Fudan University, Shanghai, 200433, P. R. China
| | - Kai Hu
- Department of Materials Science, Fudan University, Shanghai, 200433, P. R. China
| | - Weixin Ouyang
- Department of Materials Science, Fudan University, Shanghai, 200433, P. R. China
| | - Xiaosheng Fang
- Department of Materials Science, Fudan University, Shanghai, 200433, P. R. China
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54
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Srinivasan S, Balasubramanian G. Reduced Thermal Transport in the Graphene/MoS 2/Graphene Heterostructure: A Comparison with Freestanding Monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:3326-3335. [PMID: 29429341 DOI: 10.1021/acs.langmuir.7b03974] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The thermal conductivity of the graphene-encapsulated MoS2 (graphene/MoS2/graphene) van der Waals heterostructure is determined along the armchair and zigzag directions with different twist angles between the layers using molecular dynamics (MD) simulations. The differences in the predictions relative to those of the monolayers are analyzed using the phonon power spectrum and phonon lifetimes obtained by spectral energy density analysis. The thermal conductivity of the heterostructure is predominantly isotropic. The out-of-plane phonons of graphene are suppressed because of the interaction between the adjacent layers that results in the reduced phonon lifetime and thermal conductivity relative to monolayer graphene. The occurrence of an additional nonzero phonon branch at the Γ point in the phonon dispersion curves of the heterostructure corresponds to the breathing modes resulting from stacking of the layers in the heterostructure. The thermal sheet conductance of the heterostructure being an order of magnitude larger than that of monolayer MoS2, this van der Waals material is potentially suitable for efficient thermal packaging of photoelectronic devices. The interfacial thermal conductance of the graphene/MoS2 bilayer as a function of the heat flow direction shows weak thermal rectification.
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Affiliation(s)
- Srilok Srinivasan
- Department of Mechanical Engineering , Iowa State University , Ames , Iowa 50011 , United States
| | - Ganesh Balasubramanian
- Department of Mechanical Engineering & Mechanics , Lehigh University , Bethlehem , Pennsylvania 18015 , United States
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55
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Shin YS, Lee K, Kim YR, Lee H, Lee IM, Kang WT, Lee BH, Kim K, Heo J, Park S, Lee YH, Yu WJ. Mobility Engineering in Vertical Field Effect Transistors Based on Van der Waals Heterostructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30. [PMID: 29333683 DOI: 10.1002/adma.201704435] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/30/2017] [Indexed: 06/07/2023]
Abstract
Vertical integration of 2D layered materials to form van der Waals heterostructures (vdWHs) offers new functional electronic and optoelectronic devices. However, the mobility in vertical carrier transport in vdWHs of vertical field-effect transistor (VFET) is not yet investigated in spite of the importance of mobility for the successful application of VFETs in integrated circuits. Here, the mobility in VFET of vdWHs under different drain biases, gate biases, and metal work functions is first investigated and engineered. The traps in WSe2 are the main source of scattering, which influences the vertical mobility and three distinct transport mechanisms: Ohmic transport, trap-limited transport, and space-charge-limited transport. The vertical mobility in VFET can be improved by suppressing the trap states by raising the Fermi level of WSe2 . This is achieved by increasing the injected carrier density by applying a high drain voltage, or decreasing the Schottky barrier at the graphene/WSe2 and metal/WSe2 junctions by applying a gate bias and reducing the metal work function, respectively. Consequently, the mobility in Mn vdWH at +50 V gate voltage is about 76 times higher than the initial mobility of Au vdWH. This work enables further improvements in the VFET for successful application in integrated circuits.
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Affiliation(s)
- Yong Seon Shin
- Department of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon-si, 16419, Republic of Korea
| | - Kiyoung Lee
- Samsung Advanced Institute of Technology, Suwon-si, Gyeonggi-do, 443-803, Republic of Korea
| | - Young Rae Kim
- Department of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon-si, 16419, Republic of Korea
| | - Hyangsook Lee
- Samsung Advanced Institute of Technology, Suwon-si, Gyeonggi-do, 443-803, Republic of Korea
| | - I Min Lee
- Department of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon-si, 16419, Republic of Korea
| | - Won Tae Kang
- Department of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon-si, 16419, Republic of Korea
| | - Boo Heung Lee
- Korea Electronics Technology Institute, Seongnam, 13509, Republic of Korea
| | - Kunnyun Kim
- Korea Electronics Technology Institute, Seongnam, 13509, Republic of Korea
| | - Jinseong Heo
- Samsung Advanced Institute of Technology, Suwon-si, Gyeonggi-do, 443-803, Republic of Korea
| | - Seongjun Park
- Samsung Advanced Institute of Technology, Suwon-si, Gyeonggi-do, 443-803, Republic of Korea
| | - Young Hee Lee
- Department of Energy Science, Department of Physics and Center for integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon-si, 16419, Republic of Korea
| | - Woo Jong Yu
- Department of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon-si, 16419, Republic of Korea
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56
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Zhou N, Wang R, Zhou X, Song H, Xiong X, Ding Y, Lü J, Gan L, Zhai T. P-GaSe/N-MoS 2 Vertical Heterostructures Synthesized by van der Waals Epitaxy for Photoresponse Modulation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:1702731. [PMID: 29319224 DOI: 10.1002/smll.201702731] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/15/2017] [Indexed: 05/21/2023]
Abstract
The important role of p-n junction in modulation of the optoelectronic properties of semiconductors is widely cognized. In this work, for the first time the synthesis of p-GaSe/n-MoS2 heterostructures via van der Waals expitaxial growth is reported, although a considerable lattice mismatching of ≈18% exists. According to the simulation, a significant type II p-n junction barrier located at the interface is expected to be formed, which can modulate optoelectronic properties of MoS2 effectively. It is intriguing to reveal that the presence of GaSe can result in obvious Raman and photoluminescence (PL) shift of MoS2 compared to that of pristine one, more interestingly, for PL peak shift, the effect of GaSe-induced tensile strain on MoS2 has overcome the p-doping effect of GaSe, evidencing the strong interlayer coupling between GaSe and MoS2 . As a result, the photoresponse rate of heterostructures is improved by almost three orders of magnitude compared with that of pristine MoS2 .
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Affiliation(s)
- Nan Zhou
- State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Renyan Wang
- State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Xing Zhou
- State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Hongyue Song
- School of Physics, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Xing Xiong
- State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Yao Ding
- Department of Chemical and Biological Engineering, Hong Kong University of Science and Technology (HKUST), Hong Kong, P. R. China
| | - Jingtao Lü
- School of Physics, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Lin Gan
- State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
| | - Tianyou Zhai
- State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China
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57
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Khanaki A, Tian H, Xu Z, Zheng R, He Y, Cui Z, Yang J, Liu J. Effect of high carbon incorporation in Co substrates on the epitaxy of hexagonal boron nitride/graphene heterostructures. NANOTECHNOLOGY 2018; 29:035602. [PMID: 29165320 DOI: 10.1088/1361-6528/aa9c58] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We carried out a systematic study of hexagonal boron nitride/graphene (h-BN/G) heterostructure growth by introducing high incorporation of a carbon (C) source on a heated cobalt (Co) foil substrate followed by boron and nitrogen sources in a molecular beam epitaxy system. With the increase of C incorporation in Co, three distinct regions of h-BN/G heterostructures were observed from region (1) where the C saturation was not attained at the growth temperature (900 °C) and G was grown only by precipitation during the cooling process to form a 'G network' underneath the h-BN film; to region (2) where the Co substrate was just saturated by C atoms at the growth temperature and a part of G growth occurs isothermally to form G islands and another part by precipitation, resulting in a non-uniform h-BN/G film; and to region (3) where a continuous layered G structure was formed at the growth temperature and precipitated C atoms added additional G layers to the system, leading to a uniform h-BN/G film. It is also found that in all three h-BN/G heterostructure growth regions, a 3 h h-BN growth at 900 °C led to h-BN film with a thickness of 1-2 nm, regardless of the underneath G layers' thickness or morphology. Growth time and growth temperature effects have been also studied.
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58
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Li F, Wei W, Zhao P, Huang B, Dai Y. Electronic and Optical Properties of Pristine and Vertical and Lateral Heterostructures of Janus MoSSe and WSSe. J Phys Chem Lett 2017; 8:5959-5965. [PMID: 29169238 DOI: 10.1021/acs.jpclett.7b02841] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
On the basis of electron-electron self-energy corrections, quasiparticle band structures of Janus MoSSe and WSSe are identified, and the excitonic effects are demonstrated to play a dominate role in the optical response. Combining together MoSSe and WSSe monolayers to form vertical heterostructures (VHTs) and lateral heterostructures (LHTs) rarely leads to a simple arithmetic sum of their properties, giving rise to novel and unexpected behaviors. In particular, Rashba polarization can be enhanced in VHTs due to improved out-of-plane electric polarity. In the case of LHTs, photoresponse and absorption coefficients show optical activity in a wide visible light range. It is of interest that both VHTs and LHTs reveal type-II band alignment, enabling the separation of excitons. Besides, grain boundaries (GBs) of large angle (60°) in Janus MoSSe due to chalcogen effects behave as one-dimensional (1D) metallic quantum wires, suggesting the possible formation of 1D electron or hole gas in such electronic heterostructures.
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Affiliation(s)
- Fengping Li
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan 250100, China
| | - Wei Wei
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan 250100, China
| | - Pei Zhao
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan 250100, China
| | - Baibiao Huang
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan 250100, China
| | - Ying Dai
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University , Jinan 250100, China
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59
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Zhao J, Cheng K, Han N, Zhang J. Growth control, interface behavior, band alignment, and potential device applications of 2D lateral heterostructures. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2017. [DOI: 10.1002/wcms.1353] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Jijun Zhao
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology); Ministry of Education; Dalian China
| | - Kai Cheng
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology); Ministry of Education; Dalian China
| | - Nannan Han
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology); Ministry of Education; Dalian China
| | - Junfeng Zhang
- School of Physics and Information Engineering; Shanxi Normal University; Linfen China
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60
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Zhang H, Wen H, Liu Z, Zhang Q, Xie H. TEM nano-Moiré evaluation for an invisible lattice structure near the grain interface. NANOSCALE 2017; 9:15923-15933. [PMID: 29019497 DOI: 10.1039/c7nr04262k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Moiré technique is a powerful, important and effective tool for scientific research, from the nano-scale to the macro-scale, which is essentially the interference between two or more periodic structures with a similar frequency. In this study, an inverse transmission electron microscopy (TEM) nano-Moiré method has been proposed, for the first time, to reconstruct an invisible lattice structure near the grain interface, where only one kind of lattice structure and Moiré fringe were visible in a high resolution TEM (HRTEM) image simultaneously. The inversion process was performed in detail. Three rules were put forward to ensure the uniqueness of the inversion result. The HRTEM image of a top-coat/thermally grown oxide interface in a thermal barrier coating (TBC) structure was observed with coexisting visible lattice and Moiré fringes. Using the inverse TEM nano-Moiré method, the invisible lower layer lattice was inversed and a 3-dimensional structure near the interface was also reconstructed to some degree. The real strain field of oriented invisible and visible lattices and the relative strain field of the Moiré fringe in the grain and near the grain boundary were obtained simultaneously through the subset geometric phase analysis method. The possible failure mechanism and position of the TBC spallation from the nano-scale to the micro-scale were discussed.
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Affiliation(s)
- Hongye Zhang
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China.
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Xia J, Zhao YX, Wang L, Li XZ, Gu YY, Cheng HQ, Meng XM. van der Waals epitaxial two-dimensional CdS xSe (1-x) semiconductor alloys with tunable-composition and application to flexible optoelectronics. NANOSCALE 2017; 9:13786-13793. [PMID: 28890983 DOI: 10.1039/c7nr04968d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Despite the substantial progress in the development of two-dimensional (2D) materials from conventional layered crystals, it still remains particularly challenging to produce high-quality 2D non-layered semiconductor alloys which may bring in some unique properties and new functions. In this work, the synthesis of well-oriented 2D non-layered CdSxSe(1-x) semiconductor alloy flakes with tunable compositions and optical properties is established. Structural analysis reveals that the 2D non-layered alloys follow an incommensurate van der Waals epitaxial growth pattern. Photoluminescence measurements show that the 2D alloys have composition-dependent direct bandgaps with the emission peak varying from 1.8 eV to 2.3 eV, coinciding well with the density functional theory calculations. Furthermore, photodetectors based on the CdSxSe(1-x) flakes exhibit a high photoresponsivity of 703 A W-1 with an external quantum efficiency of 1.94 × 103 and a response time of 39 ms. Flexible devices fabricated on a thin mica substrate display good mechanical stability upon repeated bending. This work suggests a facile and general method to produce high-quality 2D non-layered semiconductor alloys for next-generation optoelectronic devices.
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Affiliation(s)
- Jing Xia
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
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Chen F, Wang L, Ji X, Zhang Q. Temperature-Dependent Two-Dimensional Transition Metal Dichalcogenide Heterostructures: Controlled Synthesis and Their Properties. ACS APPLIED MATERIALS & INTERFACES 2017; 9:30821-30831. [PMID: 28814077 DOI: 10.1021/acsami.7b08313] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Vertically stacked and laterally stitched heterostructures consisting of two-dimensional (2D) transition metal dichalcogenides (TMDCs) are predicted to possess novel electronic and optical properties, which offer opportunities for the development of next-generation electronic and optoelectronic devices. In the present work, we report the temperature-dependent synthesis of 2D TMDC heterostructures on Si/SiO2 substrates, including MoS2-WS2, WS2-MoS2-WS2, Mo1-xWxS2-WS2, and Mo1-xWxS2 alloyed bilayer heterostructures by ambient pressure chemical vapor deposition (CVD). Raman and photoluminescence mapping studies demonstrate that the as-produced heterostructures show distinct structural and optical modulation. Our results indicate that the evolution of various 2D heterostructures originates from the competition between the adsorption and desorption of Mo atoms and the diffusion of W atoms under various growth temperatures. This work sheds light on the design and fabrication of heterostructures using controllable interfaces and junctions of diverse TMDC atomic layers.
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Affiliation(s)
- Fei Chen
- School of Materials Science and Engineering, South China University of Technology , Guangzhou 510641, China
- State Key Laboratory of Luminescent Materials and Devices, and Institute of Optical Communication Materials, South China University of Technology , Guangzhou 510641, China
| | - Lei Wang
- School of Materials Science and Engineering, South China University of Technology , Guangzhou 510641, China
| | - Xiaohong Ji
- School of Materials Science and Engineering, South China University of Technology , Guangzhou 510641, China
| | - Qinyuan Zhang
- School of Materials Science and Engineering, South China University of Technology , Guangzhou 510641, China
- State Key Laboratory of Luminescent Materials and Devices, and Institute of Optical Communication Materials, South China University of Technology , Guangzhou 510641, China
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63
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Wang B, Yang S, Wang C, Wu M, Huang L, Liu Q, Jiang C. Enhanced current rectification and self-powered photoresponse in multilayer p-MoTe 2/n-MoS 2 van der Waals heterojunctions. NANOSCALE 2017; 9:10733-10740. [PMID: 28715037 DOI: 10.1039/c7nr03445h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Vertically stacked van der Waals (vdW) heterojunctions based on two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted a great deal of attention and have created a powerful new material platform for novel, high-performance electronic and optoelectronic devices. Here, we report the construction of multilayer p-MoTe2/n-MoS2 vdW heterostructures with remarkable rectification behavior, self-powered photoresponse and distinct photosensitivity at different laser wavelengths and power densities. Field effect transistors (FETs) fabricated by MoTe2/MoS2 heterojunctions exhibit excellent gate-tunable rectification behavior and p-n junction transport characteristics, with the n-type dominating. The MoTe2/MoS2 heterojunction devices generate a self-powered photocurrent at zero bias voltage with a considerable on-off ratio reaching ∼780 and achieve a stable and fast photoresponse, due to the type-II band alignment facilitating efficient electron-hole separation. Utilizing the advantages of a p-n junction with type-II band alignment, this MoTe2/MoS2 vdW heterostructure provides more opportunities for future electronic and optoelectronic applications.
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Affiliation(s)
- Bin Wang
- School of Materials Science and Engineering, Beihang University, Beijing 100191, P.R. China.
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64
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Kaur J, Vergara A, Rossi M, Gravagnuolo AM, Valadan M, Corrado F, Conte M, Gesuele F, Giardina P, Altucci C. Electrostatically driven scalable synthesis of MoS2–graphene hybrid films assisted by hydrophobins. RSC Adv 2017. [DOI: 10.1039/c7ra09878b] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Green synthesis of MoS2/biofunctionalized graphene hybrid films assisted by Vmh2 hydrophobin for applications in biosensing and photodetection.
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Affiliation(s)
- Jasneet Kaur
- Department of Physics “Ettore Pancini”
- University of Naples Federico II
- Naples
- Italy
- Akal College of Basic Sciences
| | - Alessandro Vergara
- Department of Chemical Sciences
- University of Naples Federico II
- Naples
- Italy
- CEINGE Biotecnologie Avanzate scarl
| | - Manuela Rossi
- Department of Earth, Environment and Resources Sciences
- University of Naples Federico II
- Naples
- Italy
| | - Alfredo Maria Gravagnuolo
- Department of Chemical Sciences
- University of Naples Federico II
- Naples
- Italy
- Division of Pharmacy and Optometry
| | | | - Federica Corrado
- Istituto Zooprofilattico Sperimentale del Mezzogiorno
- Portici
- Italy
| | | | - Felice Gesuele
- Department of Physics “Ettore Pancini”
- University of Naples Federico II
- Naples
- Italy
| | - Paola Giardina
- Department of Chemical Sciences
- University of Naples Federico II
- Naples
- Italy
| | - Carlo Altucci
- Department of Physics “Ettore Pancini”
- University of Naples Federico II
- Naples
- Italy
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