Polymer Electrolyte Composite Membrane Based on Molecular Sieve 13X Mixed with Sulfonated Poly(ether ketone ether sulfone)/Poly(phenylene ether ether sulfone) Blended Membrane for Use in Direct Methanol Fuel Cell

Blend membranes between sulfonated poly(ether ketone ether sulfone) (S-PEKES) and poly(phenylene ether ether sulfone) (PPEES) were fabricated at various mole ratios. Interestingly, increasing the hydrophobic PPEES in S-PEKES/PPEES blend membranes led to the decreases in water uptake (%) when compared to S-PEKES. Incorporation of molecular sieve 13X drastically improved proton conductivity. Methanol permeability slightly decreased with molecular sieve 13X. The composite membrane with the 15% v/v molecular sieve 13X content showed the highest proton conductivity of 1.44x10(-2)S/cm which is four times higher than Nafion 117. Thus, the blending between S-PEKES and PPEES can help to decrease methanol permeability, and incorporating molecular sieve 13X can enhance proton conductivity.