Synergistic effects of highly selective ionic liquid confined in nanocages: Exploiting the three component mixed matrix membranes for CO2 capture

•Modification of ZIF-67 with highly selective 3-(trimethoxysilyl)propan-1-aminium acetate.•Simultaneous increase in CO2/CH4 and CO2/N2 selectivity and CO2 permeability.•Enhanced CO2 solubility owing to the molecular sieving of ZIF-67 and CO2 selective properties of RTIL.