Introduction of cobalt vacancies in nickel-cobalt bimetallic oxide hollow multi-shell microspheres for peroxymonosulfate activation: Synergistic interaction of high-valent cobalt-oxygen species with singlet oxygen.

The strategic engineering of spinel-derived Fenton-like catalysts for persulfate activation via non-radical pathways presents significant potential for advanced water remediation technologies. In this paper, a hollow multi-shell (HMs) catalyst with cationic cobalt vacancy (NiCo/HMs) was designed by combining the sequential template method and strong alkali etching method, and was used for peroxymonosulfate (PMS) activation. The NiCo/HMs/PMS system achieved 95.