Photocatalytic N-formylation of amines with CO₂ over Pt-Bi bimetallic decorated CeO_2−x

N-formylation of amines with CO₂ is a promising approach to high-efficient utilization of CO₂ as C1 feedstock, while conventional thermocatalytic processes suffer from harsh reaction condition and intense energy consumption. In this work, photocatalytic N-formylation of amines with CO₂ is achieved at room temperature over Pt-Bi/CeO_2−x composite catalyst. The Pt-Bi bimetallic sites increase the concentration of surface oxygen vacancies. Furthermore, the synergistic effects of Pt and Bi improve the light absorption capacity, reduce the band gap energy of the photocatalyst and promote the separation of photoinduced charge carriers. Using PhSiH₃ as the reducing agent, the conversion of N-methylaniline reaches 100 % after 3 h irradiation in N, N-dimethylformamide solvent with a N-methylformanilide selectivity of 90.8 %. The composite photocatalyst shows promising cycling stability and universality.