Morphological investigation of nafion and nafion-SiOsub(2)-hybrid membranes by SAXS analysis in dry and wet environmentas

Abstract

– Nafion-SiO2 hybrid membranes were prepared by the incorporation of SiO2 into commercial Nafion 115 for applications as electrolytes in proton exchange membrane fuel cells (PEMFC) operating at high temperature (~130ºC). These hybrids were produced by conventional in-situ sol-gel method using Tetraethyl Ortosilicate (TEOS) as the silicon precursor, and some synthesis parameters, such as the nature of alcohol (methanol, ethanol, and 2-propanol) used as solvent in the sol-gel reaction were evaluated. The morphological changes in polymeric matrix were analyzed by water-uptake and small angle X-ray scattering measurements (SAXS). These hybrids were tested in single cells by polarization curves at high temperature.