Thermodynamic regulation of carbon dioxide capture by functionalized ionic liquids

Carbon dioxide capture has attracted worldwide attention because CO₂ emissions cause global warming and exacerbate climate change. Ionic liquids (ILs) have good application prospects in carbon capture due to their excellent properties, which provide a new chance to develop efficient and reversible carbon capture systems. This paper reviews the recent progress in CO₂ chemical absorption by ILs, such as N-site, O-site, C-site, and multi-site functionalized ILs. The application of thermodynamic regulation methods in CO₂ capture is discussed in detail. Among them, the methods of enthalpy regulation are mainly introduced, for which different regulatory targets are proposed for single sites and multiple sites. Furthermore, the strategies of achieving entropy compensation through the design of spatial configurations are discussed. Particular attention is paid to the application of thermodynamic regulation in direct air capture (DAC) due to its great significance. The methods to improve the absorption kinetics are also outlined. Finally, the future development of carbon capture by functionalized ILs is proposed.