Enhancing Photocatalytic CO2 Reduction via Selective Photodeposition of Metal Cocatalysts on a Semiconductor

Abstract

This study investigates the effect of selective photodeposition of reduction and oxidation cocatalysts (Ag, Ni, and Co) on ASTO, enabling efficient charge separation and directed activation of CO₂. Photocatalytic tests revealed that CO was the main product over the Ag/ASTO/Co sample, with a yield of 1.61 μmol·g^-1·h^-1 and a selectivity of 63.4%. The introduction of Ni increased the CO yield by more than nine times (up to 15.2 μmol·g^-1·h^-1) and improved selectivity to 79.9%, while H₂ evolution and CH₄ formation reactions remained suppressed. The obtained results demonstrate a pronounced synergistic effect between Ag, Ni, and Co and propose an effective strategy for designing selective and efficient photocatalysts for CO₂ reduction in aqueous media without additional reagents.