Superior degradation of phenolic contaminants in different water matrices via non-radical Fenton-like mechanism mediated by surface-disordered WO₃

Heterogeneous Fenton-like catalysis mediated by solid catalyst is a promising oxidation technology for water purification. The redox reactivity, cost-effectiveness, and environmental compatibility of solid catalyst play governing roles in oxidant activation, radical generation, and pollutant degradation. Herein, the surface-disordered WO₃ (D-WO₃) functionally engineered by the unique crystalline-amorphous core–shell structure is proven to be a superior solid catalyst of heterogeneous Fenton-like catalysis for peroxymonosulfate (PMS) activation and pollutant degradation in various water matrices. Six typical phenolic and dye pollutants are effectively and selectively degraded in the D-WO₃/PMS system with much reduced matrix effects. Both radical identifying and scavenging tests elucidate the important role of non-radical ¹O₂ and mediated electron transfer during PMS activation on the D-WO₃ surface. The superior Fenton-like activity of D-WO₃ can be mainly attributed to the surface and sub-surface distorted lattice sites with finely tailored atomic and electronic structures and surface chemistry. These distorted lattice sites can thermodynamically serve as the key reactive centers of dissociative adsorption and catalytic activation for both PMS and pollutant, with high adsorption energy, strong structural activation, and smooth electron transfer. Our findings provide a new chance for heterogeneous Fenton-like catalysis mediated by transition metal oxides with high capacity, low cost, and no toxicity for promising water purification.