Electron Delocalization Refining Via Single Atom Substitution in Conjugated Organic Polymers for Enhanced Photocatalytic Co2 Conversion：Get the Big Picture from Small Details

The atom refining strategy is used for the design of COP-X (X = S, N, O) as the efficient photocatalysts for CO2 conversion. Both photoelectrochemical experiments and computational explorations demonstrate that the electron delocalization and reaction barrier can be well regulated by single atom substitution of S, N and O in the 1,3,5-triethynylbenzene linked COPs. Based on the prominent electron donating capacity of S, the fast electron transfer and prolonged lifetime of photoinduced charge carriers endow COP-S with superior photocatalytic CO2 conversion efficiency and selectivity. The CO production rate reaches 196.4 μmol g-1 h-1 without the presence of cocatalysts and sacrificial agents, which is 2.1-folds and 2.5-folds of COP-N and COP-O. In particular, the oxidization of H2O to O2 is also realized on bulk COP-S. Our explorations expand the COPs skeleton engineering toolbox and provide new guidance for the design of efficient catalysts for solar energy utilizations