Robust alkaline stability of MOFs functionalized poly (aryl ether ketone) anion exchange membranes for hydrogen fuel cells

Abstract

In this paper, poly (aryl ether ketone sulfone) polymers containing amino groups (Am-PAEKS) was synthesized via a direct polycondensation reaction, and subsequently, imidazole functionalized Am-PAEKS (Im-Am-PAEKS) was prepared by functionalized modification using chlorinated 1-allyl-3-methylimidazole. Meanwhile, cationically modified UiO-66-NH₂ metal-organic frameworks (CA-MOF) were added by cationic modification of D-UiO-66-NH₂, which were introduced into the polymer matrix as filler, composite membranes with different contents of cationic MOFs were prepared. The structures and morphologies of D-UiO-66-NH₂, CA-MOF and the composite membranes were also characterized by ¹H NMR, FT-IR, SEM and EDS. The prepared composite membranes exhibited good ionic conductivity, with a higher ionic conductivity of 0.184 S cm⁻¹ at 80 °C than that of the pure membrane (0.074 S cm⁻¹ at 80 °C). The open-circuit voltage (OCV) and peak power density of the composite membrane were respectively 0.924 V and 69.80 mW cm⁻². Meanwhile, all prepared composite membranes had excellent dimensional stability, with all membranes exhibiting a swelling ratio of less than 12%. These consequences demonstrate the composite membrane prepared in this article has a good application prospect for anion-exchange membrane fields.