Electrochemical synthesis of green oxidants O3 and H2O2 is valuable for applications, but challenges persist in enhancing the O3 and H2O2 generation activity and combined application. Herein, we modulate the surface Ni active sites and oxygen vacancy defects content in Ni-Sb-SnO2 electrocatalysts to enhance selectivity for electrochemical ozone generation (EOP) and two-electron electrochemical oxygen reduction reactions (2e⁻ ORR). The Ni active sites and oxygen vacancy defects enriched electrocatalysts resulting in an ozone faradaic efficiency of 48.1%, while non-enriched electrocatalyst obtained 90% selectivity for H2O2. Theoretical calculations revealed that Ni-Sb-SnO2 efficiently captures O2 with defective Ovac2 stabilize intermediates, facilitating O3 and H2O2 synthesis. Moreover, concerted EOP and 2e⁻ ORR enable concurrent generation of O3 and H2O2 for efficient synergistic degradation of organic pollutants, while attenuating the energy demands of the electrolyzer. This study provides an appealing strategy for the simultaneous production of O3 and H2O2 with applications in wastewater treatment.