Carbon dioxide selective mixed matrix composite membrane containing ZIF-7 nano-fillers

► ZIF-7 nano-particles have been synthesized and dispersed in a polymer matrix. ► High performance ZIF-7 mixed matrix membranes for gas separation were manufactured. ► Excellent compatibility between filler and polymer was observed. ► Defect-free membranes could be prepared by a simple coating technique. ► The CO2/CH4 selectivity could be more than doubled by the ZIF-7 nano-fillers.