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 3MLCT (metal‐to‐ligand charge transfer) to 3IL (intraligand). The hierarchical organization of 3IL 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 3IL 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. A new protocol was proposed to switch the excited state from metal‐to‐ligand charge transfer to 3IL (intraligand) for dramatically improving the sensitizing ability of metal–organic frameworks (MOFs). Hierarchical integration of single‐site catalysts into 3IL MOFs can directionally and rapidly steer electron transfer, leading to an extremely high H2 evolution activity and a record HCOOH yield among all the MOF photocatalysts.