Highly coupled MnO2/Mn5O8 Z-scheme heterojunction modified by Co3O4 co-catalyst: An efficient and stable photocatalyst to decompose gaseous benzene

Abstract

MnOx Z-scheme heterojunction exhibits a strong redox capacity, thereby it has great potential in the field of photocatalysis for gaseous benzene oxidation to address environmental pollution. However, the self-oxidation of MnOx due to the accumulation of photogenerated holes severely restricts its practical application. Herein, a highly coupled MnO2/Mn5O8 Z-scheme heterojunction modified by Co3O4 co-catalyst grown on ammoniated carbon cloth (MnOx/Co3O4@ACC) was constructed through electrodeposition and applied for efficient photocatalytic benzene degradation. The optimized MnOx/Co3O4@ACC presents high-efficient degradability, mineralization rate and high stability after 60 cycles (30 h). Co3O4 served as a hole collector to promote the extraction of photogenerated holes from the MnOx surface, suppressing the photocorrosion of MnOx. Additionally, the by-product CO was more easily absorbed and activated on MnOx/Co3O4@ACC surface due to the introduction of Co3O4. The electrodeposition-photocatalysis strategy developed in this work shows great application prospects for environmental contaminant remediation.