LAUSR

Abstract Although photocatalytic CO 2 reduction has been investigated extensively, veritably efficient “CO 2 photo-converter” that can be in particular operated at all-inorganic reaction system with good durability is very few. Herein, we show that photocatalytic CO 2 reduction rate over colloidal ZnS in all-inorganic aqueous environment can be improved by 1–2 orders of magnitude and reach exceptional performance after continuous regulation of reaction medium and grafting efficient cocatalysts. In the optimized condition, Cd 2+ modified colloidal ZnS exhibited 95% HCOOH selectivity with 76% apparent quantum efficiency (280 nm). A modulated reaction medium maximizes the concentration of active reaction species and maintains efficient and stable photocatalytic reaction rate, while the cocatalyst significantly improves the separation of photo-excited carriers and CO 2 reduction rate with targeted product selectivity. The present reaction system is much superior over the widely used inorganic reaction system with low CO 2 conversion ability and organic complex photocatalysts with respect to long term reaction durability.