Discrete Zr‐O Clusters Active Sites for Efficient Photocatalytic CO 2 Reduction

ABSTRACT In the field of photocatalytic CO 2 reduction for the production of high‐value‐added chemicals, designing interface electron‐transfer channels at the atomic/molecular scale that simultaneously enable the generation of high‐energy electrons, efficient electron transfer, and high stability remains a critical challenge. In this study, a MOF material named Zr‑BTB, in which the metal active centers exist in the form of discrete low‑nuclearity metal‑oxo clusters, was synthesized via a simple solvothermal method. The discrete metal centers endow Zr‑BTB with unique discretized molecular orbital characteristics, which facilitate the generation of highly reductive high‑energy electron. Moreover, the planar conjugation of the aromatic ligands and their π‑π interactions collectively establish an efficient electron‑transfer channel. These mechanisms were further corroborated by synchrotron radiation XAFS, ultrafast TA spectra and DFT calculations. Owing to these features, Zr‑BTB exhibits excellent CO production activity (145.66 µmol·g −1 ·h −1 ) and long‑term cycling stability over 20 h. This work provides a new design strategy for photocatalysts capable of simultaneously achieving high‑energy electrons generation and efficient electron‑transfer kinetics.