Stable Heterometallic Cluster‐Based Organic Framework Catalysts for Artificial Photosynthesis

A series of stable heterometallic Fe 2 M cluster‐based MOFs ( NNU‐31‐M , M=Co, Ni, Zn) photocatalysts are presented. They can achieve the overall conversion of CO 2 and H 2 O into HCOOH and O 2 without the assistance of additional sacrificial agent and photosensitizer. The heterometallic cluster units and photosensitive ligands excited by visible light generate separated electrons and holes. Then, low‐valent metal M accepts electrons to reduce CO 2 , and high‐valent Fe uses holes to oxidize H 2 O. This is the first MOF photocatalyst system to finish artificial photosynthetic full reaction. It is noted that NNU‐31‐Zn exhibits the highest HCOOH yield of 26.3 μmol g −1 h −1 (selectivity of ca. 100 %). Furthermore, the DFT calculations based on crystal structures demonstrate the photocatalytic reaction mechanism. This work proposes a new strategy for how to design crystalline photocatalyst to realize artificial photosynthetic overall reaction.