Ether-Embedded Covalent Organic Frameworks Enable Efficient Photocatalytic CO Reduction.

The photocatalytic conversion of carbon dioxide (CO) into valuable solar fuels is a promising strategy for addressing energy crises and mitigating the greenhouse effect. However, the challenge of efficiently regulating photogenerated electrons to CO active sites remains a key hurdle for high-performance CO reduction. Herein, an embedded functional group, ether group is introduced into porphyrin-triazine COFs to regulate the transfer behavior of photogenerated electrons. The ether-embedded COFs (TOT-TAPP, BOD-TAPP and QOB-TAPP) demonstrate significantly faster charge transport and higher photoactivity compared with the corresponding non-ether-embedded counterpart COFs. The theoretical calculations and in situ characterizations reveal that the ether group could not only accelerate the separation of photogenerated charge carriers, but also lead to a more substantial accumulation of electrons at the CO adsorption region (C=N imine bond), thus greatly promoting the efficiency of CO photoreduction.