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 CO 2 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 Pt 3 Co alloy nanocluster cocatalyst was loaded onto Mo 2 C MXene to enhance photocatalytic CO 2 reduction activity and CO selectivity. As anticipated, the optimized Pt 3 Co/Mo 2 C-5 exhibited a 3.2-fold increase in CO 2 -to-CO conversion efficiency compared to individual Mo 2 C MXene, with selectivity rising from 63.94% to 81.75%. The photoelectrochemical experiments and in situ transmission FTIR results further validated that the Pt 3 Co/Mo 2 C catalyst possesses excellent charge separation efficiency, providing more reduction active sites for CO 2 reduction reactions. This work offers novel insights into the utilization of alloy clusters and Mo 2 C MXene in photocatalytic CO 2 reduction.