Metal–Oxygen Bonding-Induced Structural Transition Regulation in Co-THQ for High-Performance OER
Yantao Wang, Xiaowan Bai, Junfeng Huang, Jinhua Zhang, Wangzu Li, Yu Long, Yong Peng, Jier Huang, Hua Li, Pengyi Tang, Cailing Xu
Abstract
Metal–organic frameworks (MOFs) hold significant promise as electrocatalysts for the oxygen evolution reaction (OER) owing to their tunable structure and abundant active sites. However, extensive structural transformation under operating conditions often leads to structural degradation and limited durability. Here, we report a metal–oxygen bonding-induced structural transition regulation by anchoring atomically dispersed ruthenium (Ru) onto 2D conductive MOFs (Ru–Co-THQ). X-ray absorption fine structure and PCOHP revealed that Ru incorporation modulated the local coordination and bonding environment, leading to strengthened Co/Ru–O interactions that can stabilize the MOF framework. In situ Raman and FT-IR spectroscopy revealed that this strengthened Co/Ru–O bonding retarded the reconstruction process, lowered the reconstruction potential, and facilitated the formation of high-valent Co species. As a result, Ru–Co-THQ achieved a low overpotential of 261 mV at 10 mA cm –2 in 1 M KOH, with durability exceeding 300 h and accelerated OER kinetics, outperforming IrO 2 and most cobalt-based catalysts. Theoretical calculations revealed strong orbital coupling among Co 3d, Ru 4d, and O 2p orbitals in the reconstructed phases, which modulated the electronic structure, optimized intermediate adsorption, and accelerated kinetics. This work highlights the role of metal–oxygen bonding in regulating structural transition to enhance the MOF-based electrocatalyst activity and durability, offering insights into rational design.