Development of rigid side-chain poly(ether sulfone)s based anion exchange membrane with multiple annular quaternary ammonium ion groups for fuel cells

A variety of poly (ether sulfone)s based anion exchange membranes (AEMs) rPES(x/y)-Q with high-density heterocyclic quaternary ammonium groups is prepared by a polycondensation of novel difluoro monomer with biphenol and bis(4-fluorophenyl) sulfone . The AEMs rPES(x/y)-Q exhibit low IEC values in the range of 0.82–1.33 mequiv. g −1 but relatively high hydroxide conductivity of 54.1–82.3 mS cm −1  at 80 °C. Moreover, the AEMs rPES(x/y)-Q display affordable water uptake and good stability due to their rigid side-chain, high-density and stable heterocyclic quaternary ammonium cations. Noticeably, the rPES(5/20)-MPy based single fuel cell displays a large maximum power density of 141 mW cm −2 , which reveals a potential application in anion exchange membrane fuel cell.