Conversion of CO2 to value-added products mediated by ionic liquids

Conversion of CO2 to value-added products is favorable for both greenhouse gas mitigation and carbon-resource utilization. It is still a huge challenge to efficiently, selectively, and economically convert CO2 to highly valuable products. Many reviews focusing on the catalysts and the products of CO2 transformation have been published. However, no comprehensive review of ionic liquid (IL)-mediated CO2 valorization has been published. Here, we provide a review of the IL-mediated conversion of CO2. During the conversion of CO2, ILs can act as solvents, electrolytes, CO2 absorbents, CO2 activating agents, catalysts or co-catalysts. The effects of cations, anions, alkyl chain length, and functional group of ILs, as well as temperature, pressure, other solvents, or co-catalysts on the catalytic efficiency and selectivity are discussed. We provide a comprehensive discussion of the recent experimental and theoretical progress of thermal, electrochemical and photochemical conversion of CO2 mediated by ILs and clarify the role of ILs in the process of CO2 conversion.