Leveraging Polaron Effect for Solar‐Driven Efficient Peroxymonosulfate Activation in Water Purification

Abstract Peroxymonosulfate (PMS) represents a promising advanced oxidation technique for the treatment of refractory pollutants; however, its application is limited by high costs resulting from excessive usage due to low activation efficiency. In this study, we formulated a sunlight‐driven Cu 1 –O v /TiO 2 catalyst with surface electron polaron sites to activate PMS for the degradation of contaminants, achieving a record reaction rate of k  = 2.998 min −1 even with a low PMS dosage of 0.3 mM. The adsorption process and electron transfer kinetics were significantly enhanced with surface polaron sites in Cu 1 –O v /TiO 2 , which facilitated the activation of PMS and increased the reaction rate constant k by 29.1 times compared with that of TiO 2 /PMS under illumination. Additionally, we verified that light irradiation promotes transfer from the non‐free‐radical pathway to the efficient free‐radical pathway in mechanism of PMS activation. Our designed sunlight‐driven flow‐through PMS setup achieves a removal rate exceeding 90% for 7 days of outdoor operation at 3.2 × 10 2  L m −2 h −1 , the feasibility of which is further proven in regions around the world by analysis of solar intensity. This study presents a demonstration of economical PMS application in water purification worldwide, with an estimated cost of 0.135 $ m −3 .