Reactant-Induced Dynamic Catalysis in Co Single Atom Catalyst for Efficient Water Remediation
Huan Chen, Yan Zhao, Zhe Zhang, Yukun Pan, Dawei Song, Yaqin Shi, Yanan Huang, Bo Niu, Yayun Zhang, Donghui Long
Abstract
Elucidating the dynamic evolution of single-atom catalytic sites remains a fundamental challenge in advancing single-atom catalysis. While current studies primarily focus on stimulus-responsive structural transformations induced by external perturbations (e.g., electrochemical potential variations), the intrinsic self-adaptive mechanisms of active sites under ambient reaction conditions remain largely unexplored. Here, we report a reactant-induced dynamic coordination evolution in a nitrogen/oxygen dual-coordinated cobalt single-atom catalyst (Co–N 3 O 1 ) during peroxymonosulfate-based advanced oxidation processes (PMS-AOPs). Through operando X-ray absorption spectroscopy (XAS) combined with density functional theory (DFT) calculations, we identify a two-step reversible structural transition from the initial Co–N 3 O cat configuration to an O PMS ═Co–N 3 intermediate upon PMS activation, which subsequently reverts to the original Co–N 3 O cat state during phenol oxidation. This dynamic restructuring arises from a spontaneous d – p orbital rearrangement between Co 3 d orbitals and O 2 p orbitals of coordinating oxygen species, which selectively stabilize high-valent Co(IV)═O species. The optimized catalyst exhibits a 4-fold increase in activity compared to conventional Co–N 4 SACs, along with stable operation exceeding 120 h and effective treatment of real industrial coal chemical wastewater. This work provides atomically resolved evidence of stimulus-free, reactant-induced active-site dynamics and establishes a paradigm for designing adaptive single-atom catalysts with broad applicability in environmental and energy-related applications.