Bismuth atom tailoring of indium oxide surface frustrated Lewis pairs boosts heterogeneous CO photocatalytic hydrogenation.

The surface frustrated Lewis pairs (SFLPs) on defect-laden metal oxides provide catalytic sites to activate H and CO molecules and enable efficient gas-phase CO photocatalysis. Lattice engineering of metal oxides provides a useful strategy to tailor the reactivity of SFLPs. Herein, a one-step solvothermal synthesis is developed that enables isomorphic replacement of Lewis acidic site In ions in InO by single-site Bi ions, thereby enhancing the propensity to activate CO molecules. The so-formed BiInO materials prove to be three orders of magnitude more photoactive for the reverse water gas shift reaction than InO itself, while also exhibiting notable photoactivity towards methanol production. The increased solar absorption efficiency and efficient charge-separation and transfer of BiInO also contribute to the improved photocatalytic performance. These traits exemplify the opportunities that exist for atom-scale engineering in heterogeneous CO photocatalysis, another step towards the vision of the solar CO refinery.