Engineering MoOx /MXene Hole Transfer Layers for Unexpected Boosting of Photoelectrochemical Water Oxidation

Yurou Song; Xiaomeng Zhang; Yanxue Zhang; Panlong Zhai; Zhuwei Li; Dingfeng Jin; Jiaqi Cao; Chen Wang; Bo Zhang; Junfeng Gao; Licheng Sun; Jungang Hou

doi:10.1002/anie.202200946

Engineering MoO_x /MXene Hole Transfer Layers for Unexpected Boosting of Photoelectrochemical Water Oxidation

Angew Chem Int Ed Engl. 2022 Apr 11;61(16):e202200946. doi: 10.1002/anie.202200946. Epub 2022 Feb 21.

Authors

Yurou Song¹, Xiaomeng Zhang¹, Yanxue Zhang², Panlong Zhai¹, Zhuwei Li¹, Dingfeng Jin¹, Jiaqi Cao¹, Chen Wang¹, Bo Zhang¹, Junfeng Gao², Licheng Sun^{3

4}, Jungang Hou¹

Affiliations

¹ State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, 2, Linggong Road, Dalian, 116024, P. R. China.
² Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, 2, Linggong Road, Dalian, 116024, P. R. China.
³ Center of Artificial Photosynthesis for Solar Fuels, School of Science, Westlake University, Hangzhou, 310024, P. R. China.
⁴ School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 10044, Stockholm, Sweden.

PMID: 35142021
DOI: 10.1002/anie.202200946

Abstract

The development of semiconductor photoanodes is of great practical interest for the realization of photoelectrochemical (PEC) water splitting. Herein, MXene quantum dots (MQD) were grafted on a BiVO₄ substrate, then a MoO_x layer by combining an ultrathin oxyhydroxide oxygen evolution cocatalyst (OEC) was constructed as an integrated photoanode. The OEC/MoO_x /MQD/BiVO₄ array not only achieves a current density of 5.85 mA cm^-2 at 1.23 V versus a reversible hydrogen electrode (vs. RHE), but also enhances photostability. From electrochemical analysis and density functional theory calculations, high PEC performance is ascribed to the incorporation of MoO_x /MQD as hole transfer layers, retarding charge recombination, promoting hole transfer and accelerating water splitting kinetics. This proof-of-principle work not only demonstrates the potential utilization of hole transfer layers, but also sheds light on rational design and fabrication of integrated photoanodes for feasible solar energy conversion.

Keywords: Hole Transfer Layer; Integrated Photoanode; MXene Quantum Dots; Photoelectrochemical Water Splitting; Reaction Kinetics.