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Title: Synthesis of Core/Shell WO3/WS2 Heterostructure Nanowires with Negative Photo-Responsiveness
WO3/WS2 core/shell nanowires were synthesized using a scalable fabrication method by combining wet chemical etching and chemical vapor deposition (CVD). Initially, WO3 nanowires were formed through wet chemical etching using a potassium hydroxide (KOH) solution, followed by oxidation at 650 °C. These WO3 nanowires were then sulfurized at 900 °C to form a WS2 shell, resulting in WO3/WS2 core/shell nanowires with diameters ranging from 90 to 370 nm. The synthesized nanowires were characterized using scanning electron microscopy (SEM), Raman, energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), and transmission electron microscopy (TEM). The shell is composed of 2D WS2 layers with uniformly spaced 2D layers as well as the atomically sharp core/shell interface of WO3/WS2. Notably, the WO3/WS2 heterostructure nanowires exhibited a unique negative photoresponse under visible light (405 nm) illumination. This negative photoresponse highlights the importance of interface engineering in these heterostructures and demonstrates the potential of WO3/WS2 core/shell nanowires for applications in photodetectors and other optoelectronic devices.  more » « less
Award ID(s):
2153228
PAR ID:
10617233
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Electronic Materials Letters
Date Published:
Journal Name:
Electronic Materials Letters
Volume:
21
Issue:
1
ISSN:
1738-8090
Page Range / eLocation ID:
87 to 93
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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