【文章摘要】 Nanostructured molybdenum carbide(Mo_2C) was successfully prepared from molybdenum trioxide(MoO _3) using methanothermal temperature-programmed reaction. Thermodynamic analysis indicated that in presence of methane, the formation of Mo_2 C from MoO _3 occurs through the path of MoO _3 → MoO _2 → Mo_2 C. The carburized MoO _3 was characterized using X-ray diffraction(XRD), CHNS/O analysis, Brunauer–Emmett–Teller(BET) analysis, and field-emission scanning electron microscopy(FESEM). At final carburization temperatures of 700 and 800°C and at methane contents ranging from 5vol% to 20vol%, Mo_2 C was the only solid product observed in the XRD patterns. The results indicated that the effect of methane content on the formation of the carbide phase is substantial compared with the effect of carburization time. Elemental analysis showed that at a final temperature of 700°C, the carbon content of carburized MoO _3 is very close to the theoretical carbon mass percentage in Mo_2 C. At higher carburization temperatures, excess carbon was deposited onto the surface of Mo_2 C. High-surface-area Mo_2 C was obtained at extremely low heating rates; this high-surface-area material is a potential electrocatalyst. |