Nature of surface active centers in activation of peroxydisulfate by CuO for degradation of BPA with non-radical pathway

Abstract

Nowadays, the nature of active species and the role of peroxydisulfate (PDS) was still unclear in advance oxidation systems based on activation of PDS by CuO with non-radical pathway. In this paper, a sheet like CuO containing two kinds of Cu2+ was prepared, one of which was electron deficient Cu2+ (Cu2+-h). The CuO/PDS system showed extraordinarily utilization of PDS (172.3%) for BPA degradation (after four cycles of PDS). The main degradation mechanism was dominated by non-radical pathway. SO4•- was not involved in the reaction. Cu2SO5 complex was identified as active species, which originated from PDS and two kinds of CuOx on surface of CuO. An electron deficient center [Cu(III)EDC] formed in Cu2SO5 due to the combination of Cu2+-h and PDS directly. [Cu(III)EDC] could capture electronics from pollutants and H2O, leading to the degradation of BPA and the formation of •OH. PDS was locked by two CuOx units in Cu2SO5, which explained the trace consumption during the reaction.