Review— Modern State and Prospects of Electrochemical CO₂ Conversion in Molten Salts

Abstract

An innovative environmentally friendly electrochemical method with using molten salts for direct absorption and transformation of CO2 into solid carbon-containing materials of unique structure and morphology has been developed. The paper presents a review of literature data on electrochemical conversion of carbon dioxide in molten salts as well as the authors’ research results on the direct electrochemical reduction of CO2 and Li2CO3 in chloride melts into different carbonaceous materials with added value. They include: nano-scale solid carbon of various structures and morphologies (carbon nanotubes, fibers, honeycomb-like and scaly carbon nanostructures). Several variants of CO2 electrochemical conversion have been considered, the advantages and disadvantages of each variant have been analyzed. Conditions and mechanisms of electrochemical reduction of CO2 and Li2CO3 to solid carbon are discussed. Promising applications of electrolytic carbon nanomaterials for rechargeable ion batteries, supercapacitors and catalysts are emphasized.