A critical review on persulfate-based catalytic systems: Deactivation mechanisms and regulation strategies

Catalyst deactivation remains a critical bottleneck impeding the industrial application of persulfate (PS)-based Fenton-like oxidation processes. While existing literature prioritizes activity enhancement, systematic analyses of micro-scale deactivation mechanisms and stability regulation are critically lacking. This review comprehensively evaluates deactivation phenomena and mitigation strategies in PS systems. We systematically dissect six core deactivation mechanisms driving structural damage: dissolution, coverage, agglomeration, and valence cycle obstruction at the active site; alongside substrate oxidative corrosion and pore occlusion at the support. To address the above challenges, we summarize multi-dimensional regulation strategies that prolong catalyst lifespan: active site stabilization (polarity modulation, coordination regulation, crystal facet engineering, external protection), support structure optimization (confinement effects, defect engineering, inert supports), and process optimization (washing, oxidant modification, thermal assistance). Furthermore, we synthesize the structure-performance relationships bridging deactivation and modification. Finally, we highlight frontier directions, including synchronous activity-stability enhancement, artificial intelligence-driven material screening, anti-interference in real water matrices, precise non-radical pathway regulation, and life-cycle assessments for carbon-neutral design, providing a theoretical foundation for field-ready catalysts.