Cu (II)-doped V2O5 mediated persulfate activation for heterogeneous catalytic degradation of benzotriazole in aqueous solution

Abstract Cu (II)-doped V2O5 nanoparticles were synthesized by a simple hydrothermal method and then used as heterogeneous catalysts for persulfate activation. The samples were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The obtained samples exhibited much higher activity than pure V2O5 for the degradation of benzotriazole (BTA) with persulfate. The degradation of BTA was investigated with various influencing factors including catalyst loading, Cu doping content, persulfate concentration, and pH. Free radical quenching studies revealed that both sulfate radical (SO4− ) and hydroxyl radical ( OH) contributed to BTA degradation. The highly catalytic activity of Cu-V2O5 was closely related to the synergistic effect of V (IV)/V (V) and Cu (II)/Cu (III) cycles in the persulfate activation. Furthermore, the degradation intermediates were identified by liquid chromatography-mass spectrometry and the pathways were proposed.