Contribution of Multi-Metal Oxides Based on SrMnO₃ for the Enhanced Formation of Oxygen Vacancy on Chlorobenzene Degradation: Performance and Mechanism

Background: SrMnO₃ demonstrates high efficiency in degrading chlorinated volatile organic compounds (CVOCs). However, the accumulation of chlorine species and the loss of active sites limit the further enhancement of its catalytic performance. Purpose: To improve the catalytic and chlorine poisoning resistance properties of SrMnO₃-based catalyst. Methods: A modified hydrothermal method was employed to synthesize a multi-metal-oxides catalyst based on SrMnO₃ with Ce introduced to lattice to increase surface defect density. Influences of catalyst dosage, relative humidity, pollutant concentration and airspeed on chlorobenzene (CB) removal efficiency were systematically investigated. Results: The results revealed the great removal efficiency of the multi-metal-oxides catalyst based on SrMnO₃ with T₉₀ of 247 ℃, T₉₅ of 269 ℃, and the mineralization rate of 71%. The catalytic mechanism on the catalyst was explored through comprehensive characterizations and the potential degradation pathways of CB were inferred. Conclusion: This work provides new insights into the design of metal-doped perovskite catalysts, highlighting the critical role of surface defects and oxygen vacancies in catalytic performance.