Controllable preparation of dual-phase VC-C through in-situ electroconversion for lithium storage

Transition metal carbides as promising electrode materials for lithium ions batteries (LIBs) have attracted wide attentions due to high conductivity and capacity. In this paper, dual-phase VC-C as anode materials of LIBs is designed and synthesized through green and controllable in-situ electroconversion from CO2 and NaVO3 in molten salt. Three products including dual-phase VC-C (VC-C), vanadium carbide doped by carbon (VC-DC) and carbon doped by vanadium carbide (C-DVC), are prepared by the effective regulation during molten salt electrolysis. It is confirmed that dual-phase VC-C as anode materials of LIBs exhibits the best charge/discharge performance and cycling stability. At current density of 0.1 A g-1, the stable reversible capacity can reach to 652.3 mAh g-1. Even at a high current density of 1.0 A g-1, the reversible capacity maintains about 300 mAh g-1 after 600 cycles. The capacity retention is as high as 98.4%. The average capacity loss of per cycle is only 0.0027%. The dual-phase VC-C through sustainable electroconversion from CO2 and NaVO3 in molten salt is of good promising anode materials for LIBs.