Soft nanoconfinement of ionic liquids in lyotropic liquid crystals.

Nanoconfinement of ionic liquids (ILs) influences their physicochemical properties. In this study, we investigate the effect of soft nanoconfinement imposed by lyotropic liquid crystals (LLCs) on ILs. The LLC ion gels are obtained through self-assembly of a short chain block copolymer (BCP) of polyethylene-block-poly(ethylene oxide), PE-b-PEO, in ILs. The effect of confinement on the interaction of ions with PEO is investigated through electrochemical impedance spectroscopy (EIS) and carbon dioxide (CO2) absorption measurements. The results show that the synergistic effect on the CO2 absorption capacity of LLC ion gels takes place as a result of confinement. Formation of IL pathways through the LLC increases the CO2 solubility, absorption capacity, and absorption rate. Increasing the concentration of block copolymer in the LLC structure enhances the dissociation of ILs and consequently lowers CO2 absorption. Therefore, the competing effects of confinement and IL-PEO interaction control the properties of LLC ion gels.