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

Photocatalytic COreduction reaction (CORR) is an environment-friendly technique for clean fuel generation.Developing low-cost and efficient photocatalyst/cocatalyst systems for boosting CORR is still a challenge.Herein,a novel BiOSiO/TiC2D/2D heterojunction photocatalysts are successfully prepared by in situ growth of BiOSiOon the surface of ultrathin TiCnanosheets,a kind of MXenes.The observed BiOSiO/TiC(BOSO/TC-2) hybrids exhibit a large interface contact area companied with enhanced COadsorption 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 BiOSiOnanosheets and achieve near 90%selectivity for CO over CHOH 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 COphotoreduction to solar fuels.