In situ anchoring of Cu single-atom sites into porous organic polymers for efficient overall CO2 photoreduction

Single-atom site (SAS) catalysts have been extensively investigated for their remarkable catalytic properties. However, the multistep preparation procedures are complex and difficult to control. Here, we developed a one-step in situ synthesis of Cu single atom sites anchored into two types of alkynyl-linked covalent phenanthroline frameworks (CPFs) using a facile and controllable strategy during the synthesis process, that is Cu-SASs/CPF-DBPhen and Cu-SASs/CPF-TPP. Notably, the phenanthroline ligands in Cu-SASs/CPF-DBPhen have higher opening degree than the porphyrin ligands in Cu-SASs/CPF-TPP. This allows Cu-SASs/CPF-DBPhen to achieve higher metal loading and faster charge transfer efficiency than Cu-SASs/CPF-TPP, suggesting that Cu-SASs/CPF-DBPhen may have better photocatalytic performance. As expected, the CO yield of Cu-SASs/CPF-DBPhen (similar to 21.1 mu mol<middle dot>g(-1)<middle dot>h(-1)) is about 11.7 times higher than that of CPF-DBPhen (similar to 1.8 mu mol<middle dot>g(-1)<middle dot>h(-1)) and also exceeds that of Cu-SASs/CPF-TPP (similar to 8.3 mu mol<middle dot>g(-1)<middle dot>h(-1)). Likewise, similar results were observed during the oxidation process. This work proposes a versatile one-step, in situ growth method for synthesizing catalysts.