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

ABSTRACT 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.