In-situ assembling 0D/2D Z-scheme heterojunction of Lead-free Cs2AgBiBr6/Bi2WO6 for enhanced photocatalytic CO2 reduction

Lijun Wu; Song Zheng; Heng Lin; Shun Zhou; Ahmed Mahmoud Idris; Jin Wang; Sheng Li; Zhengquan Li

doi:10.1016/j.jcis.2022.08.152

In-situ assembling 0D/2D Z-scheme heterojunction of Lead-free Cs₂AgBiBr₆/Bi₂WO₆ for enhanced photocatalytic CO₂ reduction

J Colloid Interface Sci. 2023 Jan;629(Pt A):233-242. doi: 10.1016/j.jcis.2022.08.152. Epub 2022 Aug 27.

Authors

Lijun Wu¹, Song Zheng¹, Heng Lin², Shun Zhou², Ahmed Mahmoud Idris³, Jin Wang², Sheng Li¹, Zhengquan Li⁴

Affiliations

¹ Department of Physics, Zhejiang Normal University, Jinhua, Zhejiang 321004, PR China.
² Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University, Jinhua, Zhejiang 321004, PR China.
³ Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University, Jinhua, Zhejiang 321004, PR China. Electronic address: ahmed503@zjnu.edu.cn.
⁴ Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University, Jinhua, Zhejiang 321004, PR China; Department of Physics, Zhejiang Normal University, Jinhua, Zhejiang 321004, PR China. Electronic address: ahmed503@zjnu.edu.cn.

PMID: 36081204
DOI: 10.1016/j.jcis.2022.08.152

Abstract

All-inorganic lead-free halide double perovskites have emerged as rising star photocatalysts to substitute the toxic lead-based hailed perovskites (LHPs) owing to their unique photophysical properties. Nevertheless, their photocatalytic activities toward CO₂ reduction are still far from comparable with the LHPs, associated with severe charge recombination and sluggish surface catalytic reaction. Herein, a delicate 0D/2D heterojunction of Cs₂AgBiBr₆/Bi₂WO₆ (CABB/BWO) was assembled by in-situ growing cubic CABB nanocrystals on the flat surface of BWO nanosheets via a facile hot-injection method. Density functional theory (DFT) calculations disclose that the work function and Fermi level difference between CABB and BWO give rise to charge redistribution at the interface upon the formation of the heterojunction, creating an internal electric field (IEF). Upon light irradiation, the IEF enables the photogenerated electron transfer from BWO to CABB via direct Z-scheme electron transfer mode with striking spatial charge separation as verified by in-situ X-ray photoelectron (XPS) and electron spin resonance (ESR) spectra. Consequently, the CABB/BWO heterojunction realizes 7-fold higher photocatalytic activity than pristine CABB with significant electron consumption rate of 87.66 µmol g^-1h^-1 under simulated solar light (AM 1.5G).

Keywords: Bi(2)WO(6); CO(2) reduction; Cs(2)AgBiBr(6); Photocatalysis; Z-scheme heterojunction.