ABSTRACT Photocatalytic CO 2 conversion demands precise control over multielectron reaction pathways to achieve selective solar fuel production. Atomically dispersed Fe and Cu catalysts on TiO 2 direct divergent photoreduction outcomes—CO via Fe and CH 4 /C 2 H 6 via Cu—through modulation of CO intermediate binding. Using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), X‐ray absorption fine structure (XAFS), and density functional theory (DFT) calculations, this study unveils how metal–support interactions reshape electronic structure, stabilize key intermediates, and create oxygen vacancies that enhance CO 2 adsorption in the dark. The Cu sites further promote C─C coupling, enabling multicarbon products under mild conditions. The optimized single‐atom catalysts show up to 55.7‐fold enhancement in CO and 44.5‐fold in CH 4 yields, far surpassing pristine TiO 2 . This work illustrates how rational single‐atom design can precisely manipulate reaction pathways at the atomic scale, offering a unified framework for selective photoredox catalysis in CO 2 reduction.
Kim et al. (Thu,) studied this question.