Study on reduction of MoS_2 powders with activated carbon to produce Mo_2C under vacuum conditions

A method of preparing Mo_2C via vacuum carbothermic reduction of MoS_2 in the temperature range of 1350–1550°C was proposed. The effects of MoS_2-to-C molar ratio(a, a = 1:1, 1:1.5, and 1:2.5) and reaction temperature(1350 to 1550°C) on the reaction were studied in detail. The phase transition, morphological evolution, and residual sulfur content of the products were analyzed by X-ray diffraction, field-emission scanning electron microscopy, and carbon–sulfur analysis, respectively. The results showed that the complete decomposition of MoS_2 under vacuum is difficult, whereas activated carbon can react with MoS_2 under vacuum to generate Mo_2C. Meanwhile, higher temperatures and the addition of more carbon accelerated the rate of carbothermic reduction reaction and further decreased the residual sulfur content. From the experimental results, the optimum molar ratio α was concluded to be 1:1.5.