1. China Univ Geosci, Sch Mat Sci & Technol, Beijing Key Lab Mat Utilizat Nonmetall Minerals &, Natl Lab Mineral Mat, Beijing 100083, Peoples R China
2. NIMS, Int Ctr Mat Nanoarchitecton WPI MANA, 1-1 Namiki, Tsukuba, Ibaraki 3050044, Japan
折叠
Abstract
In this work, a novel van der Waals (vdW) heterojunction composite combining g-C3N4 with nitrogen vacancies and Tp-Tta COF manifests effective interface contact area and excellent photocatalytic CO2 reduction performance. First-principles density functional theory calculation and experimental results suggest that the presence of nitrogen vacancies in g-C3N4 can widen the Fermi level gap between C3N4 (NH) and Tp-Tta COF, promoting the recombination of invalid photogenerated carriers through S-scheme pathway. Benefitted from the accelerated transfer of photogenerated charges at the vdW heterostructure interface, the deactivation of oxygen vacancies in C3N4 (NH)/COF is prevented and much higher photocatalytic activity and stability are obtained. The efficient electron transfer and the affinity of Tp-Tta for CO2 are beneficial to the enhanced CO selectivity. This work provides insights for the design of S-scheme heterojunction photocatalyst for CO2 reduction.