Abstract: To enhance the activity of molybdenum furnace conversion agents under low-temperature reaction conditions, this study optimized the preparation process of Mo₂C/AC catalysts via impregnation-carbothermal reduction by employing hydrothermal strengthening. The catalysts’ structures were characterized by N₂ physisorption-desorption, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The effects of hydrothermal strengthening on the catalyst structure and its catalytic performance in the conversion of NO₂ to NO were thoroughly investigated. The results indicated that after hydrothermal treatment, the specific surface area of the samples decreased to varying degrees, while the average pore size increased. The hydrothermal treatment induced surface reconstruction of the catalyst, and when the hydrothermal treatment temperature was controlled at 120 ℃, the catalyst had the lowest degree of defects, and the Mo content and N content on the surface reached the maximum value. Notably, the pyridinic nitrogen content, which is favorable for NO₂ adsorption, was significantly higher than that of other samples. At a reaction temperature of 50 ℃, the NO₂ conversion rate reached 100%.