PBI nanofiber mat-reinforced anion exchange membranes with covalently linked interfaces for use in water electrolysers

Anion exchange membranes (AEM) are key components in anion membrane water electrolysers. Recently developed materials less susceptible to the alkaline degradation of polymer backbone and quaternary ammonium groups. A remaining challenge is mechanical stability contact with hot dimensional when temperature feed solution changes. One reinforce a porous support. Since support like PEEK or PTFE have different swelling behavior than matrix no strong interactions matrix, voids can form, gas crossover increases. In this work, we approach issue by pore filling polybenzimidazole nanofiber mats bromomethylated precursor mTPN, an ultra-stable AEM material. During drying, covalent interaction between (PBI amine groups) (-CH2Br) established. After quaternization, optimized PBI/mTPN-50.120 composite still shows high conductivity 62 mS cm?1, but 37% reduced length comparison non-reinforced membrane. Tensile strength Young's modulus increase 17% 56% 49 MPa 680 MPa, respectively. electrolyser, stable voltage 1.98V at 0.25 cm?2 was achieved, change resistance observed over test time 200 h (50 °C, 1 M KOH, catalysts based on Ni/Fe Mo).