Nail-like α-SnWO 4 Array Film with Increased Reactive Facets for Photoelectrochemical Water Splitting

作者：Yang Liu, Weixin Qiu, Gaoshuang He, Keke Wang, Yanqiu Wang, Long Chen, Qing Wu, Wenzhang Li, Jie Li · 发表于：The Journal of Physical Chemistry C · 年份：2022 · DOI：10.1021/acs.jpcc.2c04302 · 被引用次数：13 · 研究领域：Advanced Photocatalysis Techniques、Perovskite Materials and Applications、Luminescence Properties of Advanced Materials

α-SnWO 4 is a good candidate for photoelectrochemical (PEC) water splitting due to its suitable band position that straddles the H + /H 2 and O 2 /H 2 O redox potentials. However, its poor charge transfer ability results in unsatisfactory PEC performance. From the view of material design, a nail-like α-SnWO 4 array film was constructed by a hydrothermal method assisted by halogen ions, and the corresponding physical and PEC properties are discussed. Density functional theory (DFT) calculations were also performed to help understand the effect of halogen ions (Cl –, F – ) on the growth and exposure facet of α-SnWO 4 and the underlying mechanism of PEC performance. The existence of F – decreases the surface energy of the {100} and {001} facets, directions along which the film has better charge transfer, and the {001} facet has a lower barrier in the PEC water oxidation reaction. The α-SnWO 4 film photoanode after facet regulation presents better charge transfer ability, and the oxygen evolution rate is 0.16 μmol cm –2 h –1 . In addition, a 1.9-fold photoresponse current is obtained during unbiased PEC water splitting.