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.