Improved photostability of CuO by using WO3/CuO and BiVO4/WO3/CuO heterojunction photoelectrodes with various thermal annealing processes

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) 2023, 118(0), , pp.196-204
• Main Authors: Jeon, Seung-Hwan, Bae, Seongchan, Ryu, Hyukhyun
• Format: Article
• Language: English
• Subjects: 화학공학
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2022.11.005

In this study, WO3/CuO and BiVO4/WO3/CuO heterojunction photoelectrodes were fabricated to improvethe photoelectrochemical properties of CuO photoelectrodes. Regarding the WO3/CuO photoelectrodes,we investigated the effects of thermal annealing after CuO growth and annealing temperature afterdepositing WO3 on CuO. The sample annealed at 400 C after WO3 deposition and without annealing afterCuO growth had a higher photocurrent density than the CuO photoelectrode; however, it still had a lowphotostability of 37 %. Regarding the BiVO4/WO3/CuO photoelectrodes, we investigated the effects ofannealing on WO3/CuO and the annealing temperature and duration after BiVO4 deposition. Accordingly, we found that the light absorbance, full width at half maximum of the CuO XRD (020) peak,flat-band potential, acceptor density, and charge transfer resistance were highly dependent on theannealing duration of BiVO4. Moreover, a large improvement in photoelectrochemical properties wasobtained by fabricating BiVO4/WO3/CuO heterojunction photoelectrodes via a proper annealing process. As a result, a very high photostability of 78 % was obtained from the BiVO4/WO3/CuO photoelectrode thatwas annealed at 400 C for 20 minutes only after BiVO4 deposition without annealing after CuO and WO3depositions, which was much higher than the 21 % photostability of the CuO photoelectrode. KCI Citation Count: 0