Modulating Oxygen Vacancies in Co ₃ O ₄ via Molybdenum Doping for Enhanced Catalytic Methane Combustion

Methane, as a major component of industrial emissions and automotive exhaust, poses significant threats to ecological environments and human health. However, the low-temperature catalytic oxidation of methane still faces substantial challenges. Herein, a coprecipitation hydrothermal method was employed to dope Mo atoms into the Co3O4 lattice, effectively constructing abundant oxygen vacancies and modulating the local coordination environment. The optimized CoMo-0.05 catalyst exhibits a high methane conversion of 90% at 365 °C under a space velocity of 12,000 mL g–1 h–1, which is 37 °C lower than that of pristine Co3O4, and demonstrates excellent long-term stability and water resistance. Combined characterizations and theoretical calculations reveal that the Co-Ov-Mo active sites formed in CoMo-0.05 substantially improve the adsorption and activation of gaseous oxygen, thereby promoting C–H bond cleavage in methane and enhancing its catalytic oxidation efficiency. This work elucidates the structure–activity relationship between oxygen vacancies and catalytic activity, providing theoretical guidance for the design of methane combustion catalysts.