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 O_vac2 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.