Controlled Reconstruction of MOF via Enhanced C─O Bonding for Oxygen Evolution

Metal‐organic Frameworks (MOFs) employed for oxygen evolution reaction (OER) are plagued by structural instability driven by inherent electrochemical reconstruction. Herein, we develop for the first time a ligand engineering strategy to stabilize MOF frameworks during electrocatalytic reconstruction. Notably, experimental results reveal that the ─NO 2 group dualistically enhances catalytic performance and framework stability, which activates Fe active sites to enable efficient OER catalysis with an ultralow overpotential of 227 mV at 10 mA cm −2 , and simultaneously stabilizes the MIL‐53 framework during OER, endowing the catalyst with exceptional electrochemical stability even when operated at an ultrahigh current density of 5000 mA cm −2 . Mechanistically, density functional theory (DFT) calculations elucidate that ─NO 2 group introduction enhances C 2p and O 2p orbital overlap and reinforces bond strength, conferring robust structural stability to the MOF skeleton throughout the OER process. This work demonstrates that ligand engineered C─O bond enhancement enables controlled structural reconstruction, providing a versatile paradigm for designing MOF‐based OER electrocatalysts with both outstanding activity and stability.