Synthesis and properties of cis/trans mixtures of bis(4-hydroxyphenyl)-1,2-diphenylethylene containing sulfonated poly(ethersulfone)s proton exchange membranes

► We synthesize sulfonated poly(ether sulfone)s for PEMFC. ► We control selectively sulfonation on phenyl ring of tetraphenylethylene units. ► Increasing sulfonic group increases proton conductivity. ► High sulfonated polymer membrane exhibits similar cell performance to Nafion.