The Effect of Cross-linking Technique on Membrane Performance for Direct Methanol Alkaline Fuel Cell Application

Abstract

In this study, anion exchange membranes (AEM) based on poly(vinyl alcohol) (PVA) were prepared by two different cross-linking techniques and the effects of application sequence of thermal and chemical cross-linking technique on properties of AEM were investigated. Poly(ethylene glycol) diglycidly ether (PEGDGE) was used as a chemical cross-linking agent instead of the commonly used glutaraldehyde (GA). Evaluation of the fuel cell-related properties of the prepared membranes showed that the technique of cross-linking and the application sequence of techniques affected the properties of membranes. Promisingly, it was found that the membranes prepared by firstly chemical cross-linking and then thermal cross-linking at 150˚C (PPP150) exhibited high ionic conductivity (47 mS/cm), membrane selectivity values (89 x104 S.s/cm3) and sufficient mechanical strength. These encouraging results indicate that AEMs-based on PVA cross-linked by chemical technique with PEGDGE and then thermal technique may be considered as a promising membrane for Direct Methanol Alkaline Fuel Cell (DMFC) applications.