Construction of BiVO4/NiCo2O4 nanosheet Z-scheme heterojunction for highly boost solar water oxidation

Jiafu Qu; Xiaogang Yang; Chunxian Guo; Yahui Cai; Zuoxi Li; Jundie Hu; Chang Ming Li

doi:10.1016/j.jcis.2022.01.049

Construction of BiVO₄/NiCo₂O₄ nanosheet Z-scheme heterojunction for highly boost solar water oxidation

J Colloid Interface Sci. 2022 May:613:265-275. doi: 10.1016/j.jcis.2022.01.049. Epub 2022 Jan 10.

Authors

Jiafu Qu¹, Xiaogang Yang¹, Chunxian Guo¹, Yahui Cai², Zuoxi Li¹, Jundie Hu³, Chang Ming Li⁴

Affiliations

¹ School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, PR China.
² College of Materials Science and Engineering, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, PR China.
³ School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, PR China. Electronic address: hjd@usts.edu.cn.
⁴ School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, PR China; Institute of Advanced Cross-field Science and College of Life Science, Qingdao University, Qingdao 20671, PR China; Institute of Clean Energy & Advanced Materials, Southwest University, Chongqing 400715, PR China. Electronic address: ecmli@swu.edu.cn.

PMID: 35042027
DOI: 10.1016/j.jcis.2022.01.049

Abstract

The sluggish water oxidation process is a severe obstacle for solar-driven water splitting. Therefore, it is imperative to develop a suitable photocatalyst with reduced energy barrier for strong oxidation. In this study, a Z-scheme BiVO₄/NiCo₂O₄ (BVO/NCO) heterojunction system was designed by decorating ultrathin nickel-cobalt (NiCo₂O₄) spinel nanosheets on BiVO₄ as an efficient photocatalyst for water oxidation. The unique structure of the system significantly reduced the energy barrier and improved the oxidation ability of BiVO₄ to efficiently enhance the separation and transfer of the photogenerated carriers. Thus, the photocatalyst delivered an excellent O₂ evolution performance of 1640.9 μmol∙g^-1∙h^-1 and showed 124% improved efficiency as compared to pristine BiVO₄ and a quantum efficiency of 5.39% at 400 nm for O₂ evolution. Additionally, the theoretical calculations revealed that the formation of *OOH was the rate-determining step for water oxidation. The decoration with NiCo₂O₄ significantly reduced the energy barrier between *O and *OOH, which eventually improved the photocatalytic performance of BVO/NCO. The results hold great promise for the potential application of spinel-based materials in efficient photocatalytic O₂ evolution and offer fundamental insights into the design of efficient water oxidation heterojunctions.

Keywords: NiCo(2)O(4)/BiVO(4) Z-scheme heterojunction; Reduced reaction energy barrier; Tailor heterojunction structure; photocatalytic O(2) evolution.