摘要
The increasing occurrence of pesticide micropollutants highlights the need for innovative water treatment technologies,particularly for small-community and household applications.Electro-oxidation is being widely studied in this area,unfortunately,safe,stable and efficient electrocatalytic anodes without released heavy metal ions are still highly required.In this study,we fabricated a Pt/Ti anode by high energy pulse magnetron sputtering(HiPIMS-PtTi)which was used to decompose dichlorvos(DDVP)and azoxystrobin(AZX)in water.The results show that the reaction rate constant(kENR)on HIPIMS was 35.7 min-1(DDVP)and 41.3 min-1(AZX),respectively,superior to electroplating Pt/Ti anode(EP-PtTi).The identification of radicals(^(·)OH,^(1)O_(2),^(·)O_(2)-)and micro-area analyses evidenced that Pt atoms were embedded into the TiO_(2) lattice on the surface of Ti plate by high-energy ions,which resulted in more adsorbed hydroxyls,and higher production of·OH under polarization conditions.Besides,the electro-oxidation intermediates of DDVP and AZX were identified and the degradation pathways were speculated:(1)indirect oxidation dominated by·OH attack,and(2)direct electron transfer reaction of pesticides on the anode surface.The cooperated reactions achieve the complete degradation and highly efficient mineralization of DDVP and AZX.
基金
supported by National Natural Science Foundation of China(No.21777009)
Beijing Natural Science Foundation(No.8182031).
