Co-activation of persulfate by cation and anion from FeP for advanced oxidation processes

Abstract In this study, a new strategy about cation and anion co-activation of persulfate (PS) is discovered. A novel material of iron phosphide (FeP) is prepared via phosphidation method and used for PS activation. The FeP exhibits the highest activity for degradation (99.5 %) and mineralization (79.5 %) of ibuprofen within 120 min. The superior activity of FeP is due to the abundant Feα+ in FeP, which can directly activate PS and accelerates the Fe3+/Fe2+ cycle by electron transfer between Feα+ and Fe3+. More importantly, the P in FeP carries partial negative charges (Pβ−). It possesses the electron-donating ability, which can also activate PS and regenerate Fe2+ from Fe3+. Consequently, cation Fe and anion P can contribute co-activation of PS for effective pollution degradation. Therefore, this study sheds light on the key effect of anion on PS activation, broadens the application of FeP, and also provides an innovative strategy for environmental treatments.