Modulating electronic structure of Fe site by adjacent Cu site through orbital coupling in Cu-Fe2O3 catalyst derived from Fenton sludge quenching

Abstract

The incorporation of specific atoms into catalysts derived from Fenton sludge has the potential to regulate active site for promoting peroxymonosulfate (PMS) activation. Here, quenching technology was employed in this study to facilitate the production of a highly active Fe2O3-based catalyst from Fenton sludge. In this process, Cu atoms effectively substituted Fe atoms and regulated the local electronic structure of neighbouring Fe sites, thereby enhancing the catalytic performance in PMS activation for the degradation of Levofloxacin (LEVO) in wastewater. The strong orbital coupling between Fe and Cu, as confirmed by comprehensive characterization and density functional theory (DFT), facilitated the delocalization of d-orbital electrons, thereby enabling efficient electron transfer and redox cycling of Cu2+/Cu+ and Fe3+/Fe2+. This allowed degradation reaction to proceed continuously. The present study will offer a novel approach to the design of Fenton sludge derived catalysts, thereby expanding the utilization of quenching chemistry in solid waste recycling.