LAUSR

Visible-light-driven CO2 photoreduction with H2O to value-added chemicals in high efficiency and selectivity is significant, but challenging. Herein, a series of carbazolic conjugated organic polymers (CB-COPs) with electron donor-acceptor (D-A) structures are prepared, which show high efficiency for visible-light-driven photocatalytic reduction of CO2 with H2O in a solid-gas mode, affording CO as the exclusively carbonaceous product. Especially, CB-COP-mpd derived from 3,5-di(9H-carbazol-9-yl)pyridine exhibits the highest CO evolution rate up to 191.46 μmol g-1 h-1 with a selectivity of 100%. Mechanism studies show that carbazolyl is a promising electron donor candidate for constructing CB-COPs with D-A structures, which is capable of improving the catalytic efficiency and suppressing H2 generation. The acceptor building block with excessive electron withdrawing capability is favorable to H2O adsorption, thus resulting in the generation of H2. This work provides new insights for designing COPs photocatalysts for CO2 photocatalytic reduction.