Modulating cobalt-iron electron transfer via encapsulated structure for enhanced catalytic activity in photo-peroxymonosulfate coupling system.

In recent years, many efforts have been made to modulate the interaction between carriers and nanoparticles under the integrity of the active site structure. Herein, SrFeO @CoSe nanocomposite was fabricated by loading CoSe onto SrFeO particles with a perovskite structure in the form of an encapsulation. The optimized SFO@CS-0.3 catalyst exhibited high catalytic activity in photo-peroxymonosulfate-based reaction and the catalyst was structurally stable over a wide temperature range. Characterization and theoretical results demonstrated that the charge in the SrFeO was transferred from Fe to Co cation of the CoSe via the interfacial oxygen atom. Moreover, the newly established oxygen-metal structure (Fe-O-Co) acted as a catalytic site, accelerating the cleavage of the peroxymonosulfate bond to generate radicals, which were desorbed into solution to attack the contaminant. Simultaneously, the heterojunction constructed by the catalyst underwent internal electron transfer under visible light, creating a field in which multiple reactive oxygen species co-oxidized organic contaminant.