Sulfonated silica/nafion® based composite electrospun membranes for pem fuel cells

In this study, dual electrospinning were employed to fabricate proton conducting membranes comporising sulfonated silica, Nafion® and PVDF or P(VDF-TrFE) as the carrier polymers. Firstly, dual electrospinning was carried out to obtain dual fiber-based mats and converted into compact membranes via hot-pressing. After obtaining compact membranes, effect of various amounts of Nafion and type of carrier polymers were investigated. FTIR, ionic conductivity, ion exchange capacity (IEC), water uptake measurments and mechanical test were conducted for these membranes. Finally Membrane-electrode-assemblies (MEAs) were prepared via composite electrospun membranes and sprayed electrodes and fuel cell performance tests were performed. The fuel cell test showed that presence of sulfonated silica in the composite membranes improved the performance at lower humidity conditions. The P(VDF-TrFE)-Nafion®/S-SiO2 membranes with 60/30 wt% Nafion®/S-SiO2 compositon showed the best ionic conductivity and fuel cell performance.