WO3 homojunction photoanode: Integrating the advantages of WO3 different facets for efficient water oxidation

• 作者: Minji Yang Jie Li Gaili Ke Binyao Liu Faqin Dong Long Yang Huichao He Yong Zhou
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（5）
• 页码范围: 37-45
• 页数: 9页
• 语种: 英文

摘要

The manipulation of the surface property of WO3 photoanode is the main breakthrough direction to improve its solar water oxidation performance both in thermodynamics and kinetics.Here,we report a WO3(002)/m-WO3 homojunction film that is composed of an upper WO3 layer with predominant (002) facet (WO3(002)) and a lower WO3 layer with multi-crystal facets (m-WO3) as a photoanode for solar water oxidation.Due to the synergistic effect of WO3(002) layer and m-WO3 layer,better water oxidation activity and stability are achieved on the WO3(0O2)/m-WO3 homojunction film relative to the m-WO3 and WO3(002) film.Specifically,the improved water oxidation performance on the WO3(002)/m-WO3 homojunction film is attributed to the followings.In thermodynamics,the band position differences between WO3(002) layer and m-WO3 layer lead to the formation of WO3(002)/m-WO3 homojunction,which has positive function of improving their charge separation and transfer.In kinetics,the upper WO3(002) layer of the WO3(002)/m-WO3 film has superior activity in the adsorption and activation of water molecules,water oxidation on this homojunction film photoanode is inclined to follow the four-holes pathway,and the corrosion of photoanode from the H2O2 intermediate is restrained.The present work provides a new strategy to modify the WO3 photoanodes for thermodynamically and kinetically efficient water oxidation.