Switching Excited State Distribution of Metal–Organic Framework for Dramatically Boosting Photocatalysis

Photosensitization associated with electron/energy transfer represents the central science of natural photosynthesis. Herein, we proposed a protocol to dramatically improve the sensitizing ability of metal-organic frameworks (MOFs) by switching their excited state distribution from 3 MLCT (metal-to-ligand charge transfer) to 3 IL (intraligand). The hierarchical organization of 3 IL MOFs and Co/Cu catalysts facilitates electron transfer for efficient photocatalytic H2 evolution with a yield of 26 844.6 μmol g-1 and CO2 photoreduction with a record HCOOH yield of 4807.6 μmol g-1 among all the MOF photocatalysts. Systematic investigations demonstrate that strong visible-light-absorption, long-lived excited state and ingenious multi-component synergy in the 3 IL MOFs can facilitate both interface and intra-framework electron transfer to boost photocatalysis. This work opens up an avenue to boost solar-energy conversion by engineering sensitizing centers at a molecular level.