Spatially composition-modulated two-dimensional WS2xSe2(1-x) nanosheets
Xueping Wu1, Honglai Li1, Hongjun Liu1
1Key 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.
Nanoscale
|March 23, 2017
Summary
Researchers developed a new method for creating 2D transition-metal dichalcogenides (TMDs) with tunable bandgaps. This controllable synthesis of spatially composition-modulated WS2xSe2(1-x) nanosheets and heterostructures opens doors for advanced nanophotonics.
Area of Science:
- Materials Science
- Nanotechnology
- Condensed Matter Physics
Background:
- Two-dimensional (2D) transition-metal dichalcogenides (TMDs) offer tunable bandgaps crucial for nanophotonics.
- Controlling the physical and chemical properties of these atomic layered nanostructures is essential for advanced applications.
Purpose of the Study:
- To report the controllable synthesis of spatially composition-modulated WS2xSe2(1-x) nanosheets and WS2-WS2xSe2(1-x) lateral heterostructures.
- To understand the growth mechanism of these novel 2D materials.
Main Methods:
- A developed one-step chemical vapor deposition (CVD) approach was employed for synthesis.
- Precise control of evaporation sources allowed for optical tuning of composition across the nanosheets.
- Microstructure characterization, local photoluminescence (PL), and Raman spectroscopy were used for analysis.
Main Results:
- Spatially composition-modulated WS2xSe2(1-x) nanosheets and lateral heterostructures were successfully synthesized.
- Composition varied gradually from the center to the edge of the nanosheets.
- Position-dependent optical properties, including shifts in PL peaks and Raman modes, were observed, correlating with tunable bandgaps.
Conclusions:
- The study demonstrates a novel approach for the controllable synthesis of 2D semiconductor heterostructures.
- This method provides a pathway for preparing materials with tunable compositions and bandgaps.
- The findings hold significant potential for applications in nanoelectronics and optoelectronics.
