Ionic liquids (ILs) have been widely used for CO2 separation because of their unique properties

such as negligible vapor pressure

tunability for aimed application and high solubility for CO2. However

the high viscosity and pricey cost of ILs limit their use in industrial applications. Thus

immobilization of ILs in membranes becomes one of the hot research spots in IL field due to the ILs based membranes possess both the advantages of ILs and membranes. This review summarizes the latest research on supported ionic liquid membranes

polymerized ionic liquid membranes and ionic liquid composite membranes for CO2 separation. It is also discussed how the structures of ILs and ILs contents influence on the gas separation performances and stabilities of membranes. The research indicates that ILs composite membranes have high separation performance and stability

which is one of the prospective materials for CO2 capture. The future research should highlight on the development of the novel fuctionalized ILs composite membranes and the trade-off of high CO2 permeation rate and high stability to enhance the CO2 separation performance. Besides

the study on the fabrication of composite membrane

gas transportation in membrane and CO2 separation mechanism will inevitably attract considerable attentions.