Electrochemical graphitization conversion of CO2 through soluble NaVO3 homogeneous catalyst in carbonate molten salt

s Electrochemical conversion of CO 2 to carbon in molten salts is a promising route for the high-value utilization of greenhouse gases . Low graphitization degree of carbon materials is the limiting issue for potential applications. In the past, catalytic effect for the electrochemical conversion of CO 2 was not achieved in molten salts due to carbon coverage on heterogeneous solid electrode. A novel and feasible homogeneous catalytic strategy by soluble NaVO 3 in carbonate molten salt was proposed for the enhanced electrochemical conversion of CO 2 to carbon with high graphitization degree. It was found that graphite consisting of carbon nanotubes and sheets were more easily produced by adding NaVO 3 into molten salt. The graphitization degree of carbon products was obviously improved and I D / I G value was only 0.428. During CO 2 electrolysis, vanadate in the form of V 2 O 7 4− will be co-electroreduced to V 2 O 3 . Meanwhile, V 2 O 7 4− ions can be regenerated by the spontaneous reaction between the newly-formed V 2 O 3 and carbonate, which also accelerates the production of graphite. Therefore, a continuous homogeneous in-situ catalytic cycle was achieved for the enhanced graphitization conversion of CO 2 . It provides a novel and effective way to prepare carbon materials with high graphitization degree from CO 2 .