The CuSCN layer between BiVO4 and NiFeOx for facilitating photogenerated carrier transfer and water oxidation kinetics

Jingkun Wang; Jidong Sun; Yuliang Liu; Xun Zhang; Kai Cheng; Yupeng Chen; Fangzhou Zhou; Jujie Luo; Tianbao Li; Junjie Guo; Bingshe Xu

doi:10.1016/j.jcis.2024.04.017

The CuSCN layer between BiVO₄ and NiFeO_x for facilitating photogenerated carrier transfer and water oxidation kinetics

J Colloid Interface Sci. 2024 Jul 15:666:57-65. doi: 10.1016/j.jcis.2024.04.017. Epub 2024 Apr 4.

Authors

Jingkun Wang¹, Jidong Sun¹, Yuliang Liu¹, Xun Zhang¹, Kai Cheng¹, Yupeng Chen¹, Fangzhou Zhou¹, Jujie Luo¹, Tianbao Li², Junjie Guo³, Bingshe Xu⁴

Affiliations

¹ College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
² College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China; Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030032, China. Electronic address: litianbao@tyut.edu.cn.
³ Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China. Electronic address: guojunjie@tyut.edu.cn.
⁴ Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030032, China.

PMID: 38583210
DOI: 10.1016/j.jcis.2024.04.017

Abstract

Modification of oxygen evolution co-catalyst (OEC) on the surface of bismuth vanadate (BiVO₄) can effectively improve the kinetics of water oxidation, but it is still limited by the small hole extraction driving force at the BiVO₄/OEC interface. Modulating the BiVO₄/OEC interface with a hole transfer layer (HTL) is expected to facilitate hole transport from BiVO₄ to the OEC surface. Herein, a copper(I) thiocyanate (CuSCN) HTL is inserted between BiVO₄ and NiFeO_x OEC to create BiVO₄/CuSCN/NiFeO_x photoanode, resulting in a significant enhancement of photoelectrochemical (PEC) water splitting performance. From electrochemical analyses and density functional theory (DFT) simulations, the markedly enhanced PEC performance is attributed to the insertion of CuSCN as an HTL, which promotes the extraction of holes from BiVO₄ surface and boosts the water oxidation kinetics. The optimal photoanode achieves a photocurrent density of 5.6 mA cm^-2 at 1.23 V versus the reversible hydrogen electrode (vs. RHE) and an impressive charge separation efficiency of 96.2 %. This work offers valuable insights into the development of advanced photoanodes for solar energy conversion and emphasizes the importance of selecting an appropriate HTL to mitigate recombination at the BiVO₄/OEC interface.

Keywords: BiVO(4) photoanode; Copper(I) thiocyanate; Hole transfer layer; Oxygen evolution; Photoelectrochemical water splitting.