Highly hydroxide-conductive anion exchange membrane with PIL@MOF-assisted ion nanochannels

Abstract

A highly hydroxide-conducting anion exchange membrane with well-organized multi ion channels were fabricated via incorporating poly ionic liquids modified MIL101 (PIL@MIL101) into imidazolated poly (2,6-dimethyl-1,4-phenylene oxide) (ImPPO). 1-Vinyl-3-ethylimidzolium bromine was first immobilized in MIL101 cages via supercritical fluid impregnation method. Afterwards, the rigid-assisted ion nanochannels were constructed by in-situ polymerization of ionic liquids within the long-range ordered pores of MIL101. Meanwhile, PPO was functionalized by 1-ethyl-2-methyimidzolium to prepare comb-shaped ImPPO with enhanced microphase separation structure. Then the PIL@MIL101 was combined with ImPPO to fabricate hybrid anion exchange membrane with well-organized multiple ion channels. The OH− conductivity of the hybrid membrane significantly reached 138mS/cm at 80°C (176% higher than that of pristine membrane). Furthermore, the stability and mechanical properties of the hybrid membranes were remarkably enhanced. The excellent performances render the hybrid membrane a good candidate for the application in anion exchange membrane fuel cells.