Selective solar-driven CO2 reduction mediated by 2D/2D Bi2O2SiO3/MXene nanosheets heterojunction

Photocatalytic CO2 reduction reaction (CO2RR) is an environment-friendly technique for clean fuel generation. Developing low-cost and efficient photocatalyst/cocatalyst systems for boosting CO2RR is still a challenge. Herein, a novel Bi2O2SiO3/Ti3C2 2D/2D heterojunction photocatalysts are successfully prepared by in situ growth of Bi2O2SiO3 on the surface of ultrathin Ti3C2 nanosheets, a kind of MXenes. The observed Bi2O2SiO3/Ti3C2 (BOSO/TC-2) hybrids exhibit a large interface contact area companied with enhanced CO 2 adsorption capability, illustrating excellent 2D/2D interfacial charge transfer behaviors. The total yield of products obtained on the optimized BOSO/TC-2 photocatalyst is 3.8 times that of pristine Bi2O2SiO3 nanosheets and achieve near 90 % selectivity for CO over CH3OH without sacrificial agents, which was higher than most all inorganic Bi-based photocatalysts. Moreover, the mechanism of enhanced photocatalytic activity and reaction pathway was proposed in terms of the DFT study and in situ FTIR analysis. This work might provide new semiconductor/cocatalyst systems for selective CO2 photoreduction to solar fuels. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.