LAUSR

Abstract Enhanced catalytic ozonation of di-n-butyl phthalate (DBP), a recalcitrant waterborne pollutant, was enabled by a family of novel Ag-doped spinel ferrites (MnFe2O4) materials. A sol-gel approach was used to synthesize the Ag-doped MnFe2O4 catalysts, resulting in a highly porous structure with good magnetic property. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis confirmed the incorporation of Ag into the MnFe2O4 structure. The Ag-doped MnFe2O4 significantly accelerated ozonation of DBP, and a Ag doping of 0.5% (relative to Mn) enhanced the apparent rate constants by a factor of three and two under circumneutral conditions, compared to the ozone-alone and undoped MnFe2O4 systems, respectively. Catalyst surface hydroxyl groups were identified as a critical factor for ozone decomposition and the subsequent hydroxyl radical production. Spectroscopic and electrochemical measurements showed that Ag doping enhanced DBP degradation by increasing the density of surface hydroxyl groups and promoting the electron transfer and cycling between the catalyst and ozone. The Ag-doped MnFe2O4 catalysts exhibited high stability and can be used for multiple cycles.