Enhanced Interfacial Electron Transfer by Asymmetric Cu-O v -In Sites on In 2 O 3 for Efficient Peroxymonosulfate Activation.

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 In 2 O 3 (Cu-In 2 O 3 /O v ) catalysts containing asymmetric Cu-O v -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-O v -In sites significantly stretches the O-O bond length. Meanwhile, the Cu-O v -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 SO 4 ⋅ - and ⋅OH. The degradation rate constant of tetracycline achieved by Cu-In 2 O 3 /O v is 31.8 times faster than In 2 O 3 /O v , and it shows the possibility of membrane reactor for practical wastewater treatment.