Manganese‐Based Catalysts for Peroxymonosulfate Activation: Material Design, Mechanisms, and Water Treatment Applications

ABSTRACT

This review focuses on manganese (Mn)‐based catalysts for peroxymonosulfate (PMS) activation and systematically summarizes recent advances in Mn‐based catalysts, including Mn oxides, element‐regulated materials, support‐loaded composites, and morphology‐regulated hierarchical or heterostructured catalysts. Particular attention is given to the relationships among material design, active‐site characteristics, PMS activation pathways, and water‐treatment performance. Reversible Mn(II)/Mn(III) and Mn(III)/Mn(IV) redox cycling generally favors radical pathways involving SO ₄ • ⁻ and •OH, whereas oxygen vacancies, heteroatom regulation, coordination confinement, and interfacial coupling can promote ¹ O ₂ ‐mediated oxidation and surface electron transfer. Representative Mn‐based systems commonly achieve 80%–100% pollutant removal within several minutes to 60 min, and some catalysts maintain high activity over pH 3–11 and after five or more reuse cycles. The effects of catalyst dosage, PMS concentration, pollutant loading, temperature, coexisting ions, dissolved organic matter, and real wastewater matrices are also discussed. Although Mn‐based catalysts show considerable potential for water treatment, Mn leaching, structural reconstruction, inefficient PMS utilization, catalyst recovery, and long‐term stability remain major challenges. This review provides guidance for the rational design and practical application of Mn‐based PMS activation systems.