Interfacial engineering of bimetallic sulfides-based Al2O3 pellets with remarkably boosted peroxymonosulfate activation

Accelerating the redox of M n+ /M n+1 (M = metal) and enhancing the electron transfer efficiency is of great challenges in peroxymonosulfate activation . In this study, Al 2 O 3 pellets were used as the support due to their excellent mechanical strength and thermodynamic stability. FeCoS@Al 2 O 3 pellets were firstly prepared via in-situ assembly of ZIF-67 and Al 2 O 3 pellets, followed by hydrothermal treatment and further sulfuration. Oxygen vacancy (O V ) is a kind of anion defect attributed to lattice oxygen detachment under specific conditions. A series of characterizations and experiments confirmed that FeCoS@Al 2 O 3 pellets possessed more abundant vacancies. Especially, the production of sulfur species remarkably strengthened the conversion of Fe 3+ /Co 3+ to Fe 2+ /Co 2+ that achieved 0.1985 min −1 degradation rate towards tetracycline (TC), which was higher than those of other reported catalysts. More significantly, a fluidized-column catalytic unit endowed the continuous zero discharge of TC with a flowing rate of 5 mL/min. Besides, the mechanism study indicated that the degradation pathway followed an order: 1 O 2 > O 2 · - > SO 4 · - > ·OH. This work provided a generally applicable method to design removable and highly efficient heterogeneous catalysts for wastewater treatment .