Electro-oxidation of solid CaC2 to carbon powder in molten salt

A simple method was proposed to synthesize carbon powder by electro-oxidization of solid CaC2 particles in molten salt. The electro-oxidization process was considered from both thermodynamics and dynamics. The carbon powder was systemically characterized and Li storage performance was evaluated in a half-cell configuration. The electrochemical oxidation was achieved by a special design of anode. Highly disordered carbon powder was prepared when the cell voltage was more than 0.5 V. The powder prepared at 2.0 V consisted of thin carbon flakes with a specific surface area of 720.8 m(2)center dot g(-1). The carbon powder delivers an initial reversible capacity of 932 mAh center dot g(-1) at 100 mA center dot g(-1) and a capacity of 869 mAh center dot g(-1) after 200 cycles. Good rate performance (397 mAh center dot g(-1) at 1000 mA center dot g(-1)) enables the carbon powder more attractive in the field of anode materials.