Highly selective visible-light-driven CO2 formylation of benzylamine over PtNi/ZnO photocatalyst

Photocatalytic CO 2 N -formylation of amines promises a clean and sustainable approach for CO 2 conversion. Conventional ZnO photocatalyst with high redox capability and good stability suffers from low absorption efficiency of visible light and severe recombination of photogenerated charge carriers. In this work, we present the decoration of ZnO nanosheets with bimetallic PtNi nanoparticles, demonstrating a high photocatalytic activity towards CO 2 N -formylation of benzylamine. The CO 2 adsorption capacity of ZnO is significantly improved with the modification of Pt and Ni. Meanwhile, the localized surface plasmon resonance effect of Ni enhances the absorption ability of visible light remarkably. Furthermore, the electron transfer paths from ZnO to the metals and from Ni to Pt within the bimetallic nanoparticles are proved by experimental and theoretical calculation results, which improve the separation efficiency of photoinduced electron-hole pairs. After 24 h reaction under visible light at room temperature, a benzylamine conversion of 85.0% is achieved with a high selectivity of 99.4% towards N -benzylformamide. The PtNi/ZnO photocatalyst also shows good cycling stability.