A polyvinyl alcohol/chitosan blend proton exchange membrane for direct methanol fuel cell

In this study, poly vinyl alcohol is blended with chitosan to fabricate proton exchange membrane using phase inversion method. The key parameters such as proton conductivity, methanol uptake and tensile strength were evaluated at five different proportions of the membrane. The PVA-chitosan ratio was taken as 1:5, 1:2, 1:1, 2:1 and 5:1. The resulting membranes were characterized using FTIR and TGA. The membrane displays an excellent proton conductivity of 0.0112 S/cm at a PVA-chitosan ratio 1:1, which is comparable with that of commercial Nafion membrane. From the methanol uptake value of 42.80% it can be inferred that the methanol cross over through the membrane will be less. The Thermo Gravimetric analysis of the membrane shows that the degradation of the membrane occur at 200°C -300°C which indicates that the membrane is suitable for portable applications, Also the mechanical strength of the membrane is within the desirable limit. The possibility of using this PVA-chitosan blend membrane as proton exchange membrane for direct methanol fuel cell is suggested.