Direct Conversion of Greenhouse Gas CO2 into Graphene via Molten Salts Electrolysis

Abstract Producing graphene through the electrochemical reduction of CO 2 remains a great challenge, which requires precise control of the reaction kinetics, such as diffusivities of multiple ions, solubility of various gases, and the nucleation/growth of carbon on a surface. Here, graphene was successfully created from the greenhouse gas CO 2 using molten salts. The results showed that CO 2 could be effectively fixed by oxygen ions in CaCl 2 –NaCl–CaO melts to form carbonate ions, and subsequently electrochemically split into graphene on a stainless steel cathode; O 2 gas was produced at the RuO 2 –TiO 2 inert anode. The formation of graphene in this manner can be ascribed to the catalysis of active Fe, Ni, and Cu atoms at the surface of the cathode and the microexplosion effect through evolution of CO in between graphite layers. This finding may lead to a new generation of proceedures for the synthesis of high value‐added products from CO 2 , which may also contribute to the establishment of a low‐carbon and sustainable world.