Pt₃Co Alloy Nanoclusters as Charge Separation and Reduction Sites for the Enhanced Photoreduction of CO₂ on Mo₂C MXene

The design and preparation of highly efficient and stable cocatalysts are critical for improving the photocatalytic CO₂ reduction performance. A traditional cocatalyst consists of metal nanoparticles that facilitate the separation of photoinduced electron-hole pairs and the reduction of protons. In this research, the Pt₃Co alloy nanocluster cocatalyst was loaded onto Mo₂C MXene to enhance photocatalytic CO₂ reduction activity and CO selectivity. As anticipated, the optimized Pt₃Co/Mo₂C-5 exhibited a 3.2-fold increase in CO₂-to-CO conversion efficiency compared to individual Mo₂C MXene, with selectivity rising from 63.94% to 81.75%. The photoelectrochemical experiments and in situ transmission FTIR results further validated that the Pt₃Co/Mo₂C catalyst possesses excellent charge separation efficiency, providing more reduction active sites for CO₂ reduction reactions. This work offers novel insights into the utilization of alloy clusters and Mo₂C MXene in photocatalytic CO₂ reduction.