Enhanced Interfacial Electron Transfer by Asymmetric Cu-Ov -In Sites on In2 O3 for Efficient Peroxymonosulfate Activation.

Abstract

Enhancing the peroxymonosulfate (PMS) activation efficiency to generate more radicals is vital to promote the Fenton-like reaction activity, however, how to promote the PMS adsorption and accelerate the interfacial electron transfer to boost its activation kinetics remains a great challenge. Herein, we prepared Cu-doped defect-rich In2 O3 (Cu-In2 O3 /Ov ) catalysts containing asymmetric Cu-Ov -In sites for PMS activation in water purification. The intrinsic catalytic activity is that the side-on adsorption configuration of the O-O bond (Cu-O-O-In) at the Cu-Ov -In sites significantly stretches the O-O bond length. Meanwhile, the Cu-Ov -In sites increase the electron density near the Fermi energy level, promoting more and faster electron transfer to the O-O bond for generating more SO4 ⋅- and ⋅OH. The degradation rate constant of tetracycline achieved by Cu-In2 O3 /Ov is 31.8 times faster than In2 O3 /Ov , and it shows the possibility of membrane reactor for practical wastewater treatment.