In-situ growth of highly permeable zeolite imidazolate framework membranes on porous polymer substrate using metal chelated polyaniline as interface layer

A facile and simple chelation assisted in-situ growth approach for the preparation of thin uniform metal organic framework composite membranes has been developed. Coherent zeolite imidazolate framework ZIF-7 and ZIF-67 layers were successfully grown on porous polypropylene substrate covered with metal-chelating polyaniline interface layer. These membranes exhibited a H-2 permeance of 1.6 x 10(-7) mol m(-2) s(-1) Pa-1 and an ideal H-2/CO2 separation factor of 7.9. The incorporation of the second organic linker 2-aminobenzimidazole in the ZIF-7 framework afforded ZIF-7-NH2 layer enabling gate-opening and flexibility. This new hybrid ZIF-7-NH2 membrane featured a significantly increased H-2 permeance of 4.9 x 10(-6) mol m(-2) s(-1) Pa-1 and an ideal H-2/CO2 separation factor of 10.6.