Molten Salt Electrolytic CO₂-Derived Carbon-Based Nanomaterials for Energy Storage and Electrocatalysis: A Review

The electroreduction of CO2 in molten salt presents a promising strategy for achieving decarbonization while simultaneously producing highly valuable CO2-derived carbon-based nanomaterials. Although electrolytic nanocarbons have been explored for an extended period, their applications in energy storage and as electrocatalysts still require an in-depth study. This paper initially introduces the advantages and basic mechanisms of CO2 reduction in molten salt and then discusses the progress of CO2-derived carbon-based nanomaterials. More importantly, the paper summarizes the applications in capacitors, batteries, and electrocatalysts based on research progress and material characteristics. It is highlighted that CO2-derived carbon-based nanomaterials were initially used in capacitors and batteries and have recently begun to be utilized as electrocatalysts for two-electron oxygen reduction reaction, oxygen evolution reaction, and hydrogen evolution reaction. A comprehensive understanding of the synthetic mechanisms of various CO2-derived carbon-based nanomaterials and their applications can lay a foundation for the further development of this low-carbon-footprint process.