Study on Nafion~|CeO_2 composite membrane for DMFC

In this paper,Nafion|CeO2 composite membranes were prepared by a solution casting method.The physicochemical properties of composite membranes were characterized by thermo-gravimetric analysis(TGA),X-ray diffraction(XRD) and scanning electron microscopy(SEM).The water uptake ability,proton conductivity and methanol permeability of the composite membranes were evaluated and compared with the recast Nafion membrane.The results show that the proton conductivity and the water uptake of the composite membranes are slightly lower than that of the recast Nafion membrane,and the methanol permeability of the composite membranes decreases with the increase of CeO2 contents.The composite membrane containing 5% CeO2 shows the highest selectivity(f =6.94×103 S/cm3) among the composite membranes,and it further improves the direct methanol fuel cell(DMFC) performance(78 mW/cm2) with 5 mol/L methanol feeding,compared with the recast Nafion membrane(67 mW/cm2).