Abstract：V8C7 powders were prepared by the carbothermal reduction method taking ammonium metavanadate，titanium dioxide and graphite as raw materials. The reduction process of ammonium metavanadate was investigated with combination of XRD，TG -DSC，SEM and particle analysis methods and the carbon coefficient was optimized. Results show that in the period of once low-temperature reduction， major reactions are decomposition of ammonium and formation of vanadium sub-oxides. During the second high-temperature vacuum reduction，the vanadium oxides convert to the reduction products of non-stoichiometry VCx. The lattice constants of VCx increase with carbon coefficient increasing. When the reaction temperature is 1 500 ℃ and the carbon coefficient is 0.9， single phase V8C7 is obtained with orderly arrangement of vanadium atoms and carbon atoms. The grain size is about 2.7 μm.

Keywords: ammonium metavanadate; carbothermal reduction; carbon coefficient