Pb-N Chemically Anchors CsPbBr3 on 1D Porous Tubular g-C3N4 for Enhanced Photocatalytic CO2 Reduction.

Abstract

Halide perovskite CsPbBr3 (CPB) quantum dots (QDs) are considered as a promising candidate for solar-driven CO2 conversion for their unique optoelectronic properties and suitable band structure. However, the CO2 conversion efficiency of pristine CsPbBr3 quantum dots is severely limited due to their rapid electron-hole pair recombination and insufficient active sites. In this study, by immobilizing CPB QDs onto one-dimensional (1D) porous tubular g-C3N4 (TCN), an effective 0D/1D CPB@TCN heterojunction photocatalyst for CO2 reduction is fabricated. Density functional theory (DFT) calculations combined with experimental studies demonstrate that CPB QDs are uniformly anchored on the surface of TCN through Pb-N chemical bonding, resulting in efficient separation and transfer of photogenerated carriers in CPB@TCN photocatalysts. The resultant CPB@TCN photocatalysts exhibit significantly enhanced photocatalytic activity for CO2 reduction with the highest conversion rate of 22.62 μmol·g-1·h-1, which is 5.33-times higher than that of pristine CPB QDs. This work unveils the interfacial bonding mechanism of CPB@TCN heterojunction through Pb-N chemical bond, which provides new insights for the development perovskite-based heterojunction photocatalysts.