Intrinsic Mechanism Analyses of Significantly Enhanced Photoelectrochemical Performance of the Bi2MoO6/BiVO4 System

Jing Tian; Zhuoyuan Chen; Li Ma; Jian Hou; Chang Feng; Jiangping Jing; Dongchu Chen

doi:10.1021/acs.langmuir.2c01031

Intrinsic Mechanism Analyses of Significantly Enhanced Photoelectrochemical Performance of the Bi₂MoO₆/BiVO₄ System

Langmuir. 2022 Jul 26;38(29):8906-8917. doi: 10.1021/acs.langmuir.2c01031. Epub 2022 Jul 11.

Authors

Jing Tian^{1

2

3

4}, Zhuoyuan Chen^{1

3

4}, Li Ma³, Jian Hou³, Chang Feng^{1

4}, Jiangping Jing^{1

3

4}, Dongchu Chen^{1

4}

Affiliations

¹ School of Materials Science and Hydrogen Energy, Foshan University, 18 Jiangwanyi Road, Foshan 528000, China.
² Key Laboratory of Marine Environmental Corrosion and Bio-fouling, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
³ State Key Laboratory for Marine Corrosion and Protection, Luoyang Ship Material Research Institute (LSMRI), Wenhai Road, Qingdao 266237, China.
⁴ Guangdong Key Laboratory for Hydrogen Energy Technologies, 18 Jiangwanyi Road, Foshan 528000, China.

PMID: 35816725
DOI: 10.1021/acs.langmuir.2c01031

Abstract

In this paper, the electrodeposition and hydrothermal methods were used to prepare the Bi₂MoO₆/BiVO₄ photoelectrode, and the intrinsic mechanism of significantly enhanced photoelectrochemical performance of the prepared Bi₂MoO₆/BiVO₄ heterojunction system was studied. Work functions of Bi₂MoO₆ and BiVO₄ were analyzed using a scanning Kelvin probe, and the direction of the heterojunction electric field and the transfer direction of photogenerated carriers were finally determined by the relative positions of the energy bands and the Fermi levels of Bi₂MoO₆ and BiVO₄. A type II Bi₂MoO₆/BiVO₄ heterojunction system was finally confirmed to be formed. Formation of the type II Bi₂MoO₆/BiVO₄ heterojunction system reduces the recombination efficiency of photogenerated electrons and holes and thus improves the photoelectrochemical performance. The photogenerated current density of the Bi₂MoO₆/BiVO₄ photoelectrode reaches 1.47 mA·cm^-2, which is 4.9 times that of pure BiVO₄ and thousands of times that of Bi₂MoO₆. The successful application of a scanning Kelvin probe in the verification of the heterojunction type provides theoretical and technical bases for the design and construction of efficient heterojunctions.