Electrochemical UV/Ozone process with Ni-Sb-SnO 2 /SiO x anode for degradation of micropollutants in wastewater

We investigated the synergistic effects of ozone evolution reaction (OZER) coupled with UV irradiation for degradation of O 3 -refractory micro-pollutants in electrochemical (E)-UV/O 3 process. A SiO x heterojunction layer over-coated on Ni-Sb-SnO 2 remarkably enhanced the OZER across a wide pH range (0.4 -10). The exceptional OZER efficiency was harnessed in E-UV/O 3 to increase degradation rates (by 2.5 -3.5-fold) and mineralization efficiencies (by 1.3 -3.9-fold) for 2,6-dinitrotoluene (DNT) compared to the sums under dark electrolysis and photolysis. Clarifying DNT degradation intermediates and reactive oxygen species elucidated the promoting mechanism within the reaction network of O 3 transformation to center dot OH, the principal oxidant for the supreme performance at near-neutral pH. Applicability of E-UV/O 3 was demonstrated by minuscule halate ion generation, outstanding stability and energy efficiency, and elimination of N,N -diethyl-m-toluamide (DEET) in reverse osmosis concentrates (ROC). These comprehensive findings from mechanistic studies to real applications are expected to broaden the utilization of OZER-based water treatments.