Enhanced Interfacial Electron Transfer by Asymmetric Cu‐O_v‐In Sites on In₂O₃ 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 In2O3 (Cu‐In2O3/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‐In2O3/Ov is 31.8 times faster than In2O3/Ov, and it shows the possibility of membrane reactor for practical wastewater treatment.

Symmetry or asymmetry: which one is the platform of nitrogen vacancies for alkaline hydrogen evolution

“…41,42 Furthermore, the symmetric N v site always enables a uniform charge distribution on the metal sites adjacent with N v , which leads to an inefficient electron transfer and thus sluggish kinetics for water dissociation. 43–45 The interest in the asymmetric defect state (M 1 -□-M 2 , where □ indicates an anion vacancy), compared with the symmetric defect state (M 1 -□-M 1 ), stems from its ability to polarize the H 2 O adsorbate by utilizing the charge difference between the M 1 and M 2 sites. This has been evidenced by the previous literature concerning the asymmetric oxygen vacancies.…”