Crystal facet-dependent frustrated Lewis pairs on dual-metal hydroxide for photocatalytic CO2 reduction

CO2 activation is a vital knot for CO2-mediated energy conversion and storage. Frustrated Lewis pairs (FLPs) are well confirmed to be highly efficient in CO2 activation. Here, we synthesized the single-crystal ZnSn(OH)6 cube with exposed (100) facet (Sc) and ZnSn(OH)6 octahedra with exposed (111) facet (So) and created FLPs with different acid-base distance on these exposed facets by vacuum irradiation, resulting from the light unstability of terminal hydroxyls. Our results demonstrated that the FLPs with short acid-base distance on So are more efficient activation centers due to the strong orbital interactions, well exemplifying that shortening the Lewis acid-base distance is a potential route to develop highly efficient FLPs catalysts. In addition, as an initial attempt, the combination effects between facet junction separating charges and FLPs activating molecules were proposed to accelerate CO2 reduction. Our findings may provide new insights into designing photocatalysts with highly catalytic performances.