Ag–Pt Alloy Nanoparticles Modified Zn-Based Nanosheets for Highly Selective CO2 Photoreduction to CH4

Multi-electron involved photoreduction of CO₂ to hydrocarbon fuels is a long-standing challenge, particularly in manipulating the selectivity of the target products. Here, a novel Ag–Pt bimetallic alloy on Zn-based supports by photo-deposition is designed for photocatalytic CO₂ reduction to CH₄ without any additives. This photocatalyst exhibits ≈ 98.9% selectivity for CH₄. Experimental and theoretical calculations demonstrated that the excellent performance of the photocatalyst can be attributed to the localized surface plasmon resonance effect of metals, as well as the synergistic effects of the bimetallic sites. These factors are found to be beneficial not only for capturing solar radiation and facilitating electron migration but also for promoting the adsorption and activation of CO₂ and the protonation of *CO. As a result, the photocatalyst achieved high selectivity and activity of photoreduction of CO₂ to CH₄. This work provides insights into the design of photocatalysts with highly selective target products for CO₂ reduction.