Quinoxaline-based crosslinked membranes of sulfonated poly(arylene ether sulfone)s for fuel cell applications

► Quinoxaline-based crosslinked sulfonated poly(arylene ether sulfone)s were synthesized. ► Covalent and acid-base ionic crosslinking improved the performance of polymer electrolyte membrane. ► The membranes had reasonably high proton conductivity and low methanol permeability.