Anchored Cobalt Nanoparticles on Layered Perovskites for Rapid Peroxymonosulfate Activation in Antibiotic Degradation

Abstract In the Fenton‐like reaction, revealing the dynamic evolution of the active sites is crucial to achieve the activity improvement and stability of the catalyst. This study reports a perovskite oxide in which atomic (Co 0 ) in situ embedded exsolution occurs during the high‐temperature phase transition. This unique anchoring strategy significantly improves the Co 3+ /Co 2+ cycling efficiency at the interface and inhibits metal leaching during peroxymonosulfate (PMS) activation. The Co@L‐PBMC catalyst exhibits superior PMS activation ability and could achieve 99% degradation of tetracycline within 5 min. The combination of experimental characterization and density functional theory (DFT) calculations elucidates that the electron‐deficient oxygen vacancy accepts an electron from the Co 3d‐orbital, resulting in a significant electron delocalization of the Co site, thereby facilitating the adsorption of the *HSO 5 /*OH intermediate onto the “metal‐V O bridge” structure. This work provides insights into the PMS activation mechanism at the atomic level, which will guide the rational design of next‐generation catalysts for environmental remediation.