Unraveling of cocatalysts photodeposited selectively on facets of BiVO4 to boost solar water splitting

Yu Qi; Jiangwei Zhang; Yuan Kong; Yue Zhao; Shanshan Chen; Deng Li; Wei Liu; Yifan Chen; Tengfeng Xie; Junyan Cui; Can Li; Kazunari Domen; Fuxiang Zhang

doi:10.1038/s41467-022-28146-6

Unraveling of cocatalysts photodeposited selectively on facets of BiVO₄ to boost solar water splitting

Nat Commun. 2022 Jan 25;13(1):484. doi: 10.1038/s41467-022-28146-6.

Authors

Yu Qi^#¹, Jiangwei Zhang^#¹, Yuan Kong^#², Yue Zhao¹, Shanshan Chen³, Deng Li¹, Wei Liu¹, Yifan Chen⁴, Tengfeng Xie⁴, Junyan Cui⁵, Can Li⁶, Kazunari Domen^{3

7}, Fuxiang Zhang⁸

Affiliations

¹ State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
² Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China.
³ Research Initiative for Supra-Materials (RISM), Shinshu University, 4-17-1 Wakasato, Nagano, 380-8553, Japan.
⁴ College of Chemistry, Jilin University, Changchun, Jilin, 130012, China.
⁵ School of Material Science and Engineering, Zhengzhou University, No. 100 Science Avenue, Zhengzhou, 450001, China.
⁶ State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China. canli@dicp.ac.cn.
⁷ Office of University Professors, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
⁸ State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China. fxzhang@dicp.ac.cn.

^# Contributed equally.

Abstract

Bismuth vanadate (BiVO₄) has been widely investigated as a photocatalyst or photoanode for solar water splitting, but its activity is hindered by inefficient cocatalysts and limited understanding of the underlying mechanism. Here we demonstrate significantly enhanced water oxidation on the particulate BiVO₄ photocatalyst via in situ facet-selective photodeposition of dual-cocatalysts that exist separately as metallic Ir nanoparticles and nanocomposite of FeOOH and CoOOH (denoted as FeCoO_x), as revealed by advanced techniques. The mechanism of water oxidation promoted by the dual-cocatalysts is experimentally and theoretically unraveled, and mainly ascribed to the synergistic effect of the spatially separated dual-cocatalysts (Ir, FeCoO_x) on both interface charge separation and surface catalysis. Combined with the H₂-evolving photocatalysts, we finally construct a Z-scheme overall water splitting system using [Fe(CN)₆]^3-/4- as the redox mediator, whose apparent quantum efficiency at 420 nm and solar-to-hydrogen conversion efficiency are optimized to be 12.3% and 0.6%, respectively.

Abstract

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