Suppressing photoinduced charge recombination at the BiVO4||NiOOH junction by sandwiching an oxygen vacancy layer for efficient photoelectrochemical water oxidation

Yong Peng; Minshu Du; Xingli Zou; Guohua Jia; Shella Permatasari Santoso; Xiang Peng; Wenxin Niu; Mingjian Yuan; Hsien-Yi Hsu

doi:10.1016/j.jcis.2021.10.063

Suppressing photoinduced charge recombination at the BiVO₄||NiOOH junction by sandwiching an oxygen vacancy layer for efficient photoelectrochemical water oxidation

J Colloid Interface Sci. 2022 Feb 15;608(Pt 2):1116-1125. doi: 10.1016/j.jcis.2021.10.063. Epub 2021 Oct 23.

Authors

Yong Peng¹, Minshu Du², Xingli Zou³, Guohua Jia⁴, Shella Permatasari Santoso⁵, Xiang Peng⁶, Wenxin Niu⁷, Mingjian Yuan⁸, Hsien-Yi Hsu⁹

Affiliations

¹ School of Energy and Environment, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong, China; Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518057, China.
² School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
³ State Key Laboratory of Advanced Special Steel & School of Materials Science and Engineering, Shanghai University, Shanghai 200072, PR China.
⁴ Curtin Institute of Functional Molecules and Interfaces School of Molecular and Life Sciences, Curtin University GPO Box U1987, Perth, WA 6845, Australia.
⁵ Department of Chemical Engineering, Faculty of Engineering, Widya Mandala Surabaya Catholic University, Kalijudan No. 37, Surabaya 60114, East Java, Indonesia.
⁶ Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan 430205, PR China.
⁷ State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry, Chinese Academy of Sciences 5625 Renmin Street, Changchun, Jilin 130022, PR China.
⁸ Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (RECAST), College of Chemistry, Nankai University, Tianjin, PR China.
⁹ School of Energy and Environment, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong, China; Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518057, China. Electronic address: sam.hyhsu@cityu.edu.hk.

PMID: 34749133
DOI: 10.1016/j.jcis.2021.10.063

Abstract

Nickel oxyhydroxide (NiOOH) is regarded as one of the promising cocatalysts to enhance the catalytic performance of photoanodes but suffers from serious interfacial charge-carrier recombination at the photoanode||NiOOH interface. In this work, surface-engineered BiVO₄ photoanodes are fabricated by sandwiching an oxygen vacancy (O_vac) interlayer between BiVO₄ and NiOOH. The surface O_vac interlayer is introduced on BiVO₄ by a chemical reduction treatment using a mild reducing agent, sodium hypophosphite. The induced O_vac can alleviate the interfacial charge-carrier recombination at the BiVO4||NiOOH junction, resulting in efficient charge separation and transfer efficiencies, while an outer NiOOH layer is coated to prevent the O_vac layer from degradation. As a result, the as-prepared NiOOH-P-BiVO₄ photoanode exhibits a high photocurrent density of 3.2 mA cm^-2 at 1.23 V vs. RHE under the irradiation of 100 mW/cm² AM 1.5G simulated sunlight, in comparison to those of bare BiVO₄, P-BiVO_4, and NiOOH-BiVO₄ photoanodes (1.1, 2.1 and 2.3 mA cm^-2, respectively). In addition to the superior photoactivity, the 5-h amperometric measurements illustrate improved stability of the surface-engineered NiOOH-P-BiVO₄ photoanode. Our work showcases the feasibility of combining cocatalysts with O_vac, for improved photoactivity and stability of photoelectrodes.

Keywords: Nickel oxyhydroxide; Oxygen vacancies; Photoelectrochemistry; Surface engineering.