Abstract: Molybdenum hemicarbide (Mo2C) can be widely used in steel, metal ceramics and catalyst of hydrogen involved reactions. This work reported a simple method for preparing molybdenum hemicarbide by reducing and carbonizing MoO2 with ethanol. Thermodynamic analysis was performed to predict experimental conditions for Mo2C formation in the MoO2-C2H5OH-Ar system with Ar/C2H5OH molar ratio of 6.82 (Ar was used as a carrier gas for ethanol). XRD and SEM analyses were carried out for phases’ and morphological studies. Based on the results, the reaction and carbonization routes were obtained: MoO2 was reduced and carburized directly to Mo2C in one step at lower temperatures, and first reduced to metallic Mo and then carburized to Mo2C at higher temperatures. The reduction mechanisms were proposed: the pseudomorphic transformation mechanism dominated the reaction at low temperatures, but at high temperatures, the reaction obeyed the chemical vapor transport (CVT) mechanism.
Authors: Zepeng Lv, Jie Dang, and Chenguang Bai
Keywords: MoO2, ethanol, Mo2C, reduction, carbonization