Photocatalytic CO2 reduction of CuO-Zn1-xCuxO (ZCO)/Ti3C2Tx MXene heterojunctions with enhanced interfacial charge transfer

Abstract

Photocatalytic CO2 reduction reaction (CO2RR) synthesis of recycled fuel is a promising pathway to assist the mitigating fossil fuel depletion. Finding efficient and inexpensive high performance CO2RR semiconductor photocatalysts is a giant challenge in the field of photocatalytic reduction. This work constructs the novel-designed interfacial Schottky junction of CuO-Zn1-xCuxO (ZCO)/Ti3C2Tx via electrostatic spinning and electrostatic self-assembly techniques. The catalysts exhibit tight contact heterogeneous interface companies with enhanced CO2 chemisorption capability and proved by various characterizations for efficient carrier separation and migration capacity. The optimized ZCO/Ti3C2Tx nanosheet composites significantly improved their photocatalytic performance. The best samples yielded 5.855 and 2.518 μmol g−1 h−1 of CO and CH4, which are 6 and 1.73 times higher than the conversion of ZCO, respectively, and maintain stability after four cycles without the use of sacrificial agents. In addition, the mechanism and reaction pathways of the photocatalytic process are proposed through In-situ diffuse reflectance Infrared Fourier Transform Spectroscopy (In-situ DRIFTS) and X-ray absorption near edge structure (XANES) analysis. This work provides a new semiconductor/co-catalyst system for the photocatalytic reduction of CO2 and demonstrates that Ti3C2Tx MXene is a hopeful and inexpensive co-catalyst.