Ionic Liquids-Promoted Electrocatalytic Reduction of Carbon Dioxide

The excessive consumption of global fossil fuels leads to the rapid increase of CO2 content in the atmosphere, causing serious consequences, such as global warming, which have attracted extensive attention from the international community. As a kind of abundant and inexpensive carbon resource, CO2 can be converted into high-utilization chemicals and fuels, and its resource utilization is of great significance to environmental protection and energy security. Among the many CO2 conversion technologies, electrochemical CO2 reduction (ECR) is considered to be one of the most promising methods, and it is a research hotspot in the world at present. In recent years, ionic liquids (ILs) have provided opportunities for the electroreduction of CO2 due to their unique physical and chemical properties. ILs have attracted more and more attention in the electrochemical reduction of CO2 due to their advantages of reducing reaction overpotential, inhibiting the hydrogen evolution reaction (HER), and improving product selectivity. In this paper, the research progress in recent years of ILs in electrocatalytic CO2 reduction is reviewed from three aspects: adsorption of CO2 by ILs, ILs-based electrolyte, and modification and preparation of electrodes in ILs. At the end of this paper, some issues and challenges to which more attention needs to be paid in future research were discussed as well.