Synergy of nitrogen vacancies and Fe2P cocatalyst on graphitic carbon nitride for boosting photocatalytic CO2 conversion

Photocatalytic CO2 conversion into value-added chemicals is a promising strategy to remedy the energy crisis and environmental pollution, yet developing cost-effective photocatalysts that can efficiently and selectively convert CO2 to desirable products is still a great challenge. Herein, we construct a Fe2P nanoparticles decorated on the surface of the nitrogen vacancies (NVs) modified g-C3N4 nanosheet hybrid photocatalyst (Fe2P/NVsCN) for photocatalytic conversion of CO2 to CO. The NVs can significantly improve the visible light absorption due to the formation of midgap state, and the metallic Fe2P as the cocatalyst is beneficial to promote the photo-generated charge separation and migration, impede the side reaction, in which improve the activity and selec-tivity. By adjusting the contents of Fe2P and NVsCN, the optimal 20%-Fe2P/NVsCN(1:5) sample shows an excellent CO evolution rate in visible light of 22.48 mu mol g -1h(-1) with 97.5% selectivity, which is superior to most reported g-C3N4-based photocatalysts. Furthermore, this photocatalyst also exhibits good stability due to the timely consumption of electrons, and it maintains stable CO evolution rate over 20 h. This work opens a new horizon for design and construction of active photocatalyst with high selectivity by synergistic modulating the surface vacancy and cocatalyst.