Anion exchange membranes are used in
electrolytic cells and
fuel cells to separate reactants present around the two electrodes while transporting the anions essential for the cell operation. An important example is the
hydroxide anion exchange membrane used to
separate the electrodes of a
direct methanol fuel cell (DMFC) or
direct-ethanol fuel cell (DEFC). Poly(fluorenyl-co-aryl piperidinium) (PFAP)-based anion exchange materials (electrolyte membrane and electrode binder) with high ion conductivity and durability under alkaline conditions has been demonstrated for use to extract hydrogen from water. Performance was 7.68
A/
cm2 at 2
V, some 6x the performance of existing materials. Its yield is about 1.2 times that of commercial
proton-exchange membrane technology (6 A/cm2), and it does not require the use of expensive
rare-earth elements. The system works by increasing the specific surface area. ==See also==