Spatially composition-modulated two-dimensional WS2xSe2(1-x)nanosheets.
Controllable synthesis of two-dimensional (2D) transition-metal dichalcogenides (TMDs) with tunable bandgaps is vital for their applications in nanophotonics, due to its efficient modulation of the physical and chemical properties of these atomic layered nanostructures. Here we report for the first time, the controllable synthesis of spatially composition-modulated WS2xSe2(1-x)nanosheets and WS2-WS2xSe2(1-x)lateral heterostructures by a developed one-step chemical vapor deposition (CVD) approach, as well as the understanding of their growth mechanism. During the growth, the composition was optically tuned along the plane of the atomic layered nanosheets through the precise control of evaporation sources. Microstructure characterization confirms the chemical identity of the composition modulated nanosheets, with S and Se contents gradually converting from the center to the edge. Local photoluminescence (PL) and Raman studies further demonstrate the position-dependent optical properties of the as-grown nanosheets, with the PL peak and Raman modes shifting in a wide range along the whole plane of the nanostructures, which are consistent with their tunable compositions and bandgaps. This demonstration of composition-modulated nanostructures provides a beneficial approach for the preparation of 2D semiconductor heterostructures and may open up a wide range of applications in nanoelectronics and optoelectronics.
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Xueping
X
Wu
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Honglai
H
Li
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Hongjun
H
Liu
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Xiujuan
X
Zhuang
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn and Institute of Physical and Theoretical Chemistry and LISA+, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
Xiao
X
Wang
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Xiaopeng
X
Fan
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Xidong
X
Duan
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Xiaoli
X
Zhu
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Qinglin
Q
Zhang
Institute of Physical and Theoretical Chemistry and LISA+, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
Alfred J
AJ
Meixner
Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA.
Xiangfeng
X
Duan
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronic Science, and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, P. R. China. anlian.pan@hnu.edu.cn.
Anlian
http://orcid.org/0000-0003-3335-3067
A
Pan