Fabrication and properties of poly(vinyl alcohol)-based polymer electrolyte membranes for direct methanol fuel cell applications

A series of poly(vinyl alcohol) (PVA)-based organic–inorganic crosslinked polymer electrolyte membranes with PVA and poly(methacrylic acid-2-acrylamido-2-methyl-1-propanesulfonic acid-vinyltriethoxysilicone) (PMAV) are prepared for direct methanol fuel cell applications. Fourier transform infrared (FTIR) spectroscopy measurements clearly reveal the existence of crosslinking reactions and molecular interactions in PVA–PMAV membranes. The results of TGA show that the PVA–PMAV membranes possess good thermal stability. The uptake behavior, methanol diffusion coefficient, proton conductivity and selectivity of membranes also are investigated as function of PMAV content. The results indicate that the PVA-based organic–inorganic crosslinked membranes are particularly promising to be used as polymer electrolyte membranes due to their excellent methanol barrier property, suitable proton conductivity and high selectivity.