Author/Authors :
Horvat، نويسنده , , Carmen I. and Zhu، نويسنده , , Xiaomin and Türp، نويسنده , , David and Vinokur، نويسنده , , Rostislav A. and Demco، نويسنده , , Dan E. and Fechete، نويسنده , , Radu and Conradi، نويسنده , , Oliver and Graichen، نويسنده , , Andreas and Anokhin، نويسنده , , Denis V. Ivanov ، نويسنده , , Dimitri A. and Mِller، نويسنده , , Martin، نويسنده ,
Abstract :
We report on the preparation and characterization of perfluorosulfonic acid ionomer (PFSA) – silica composite membranes using hyperbranched polyethoxysiloxane (PEOS) as silica precursor. The membranes were formed via an in situ sol–gel process of PEOS in a PFSA solution and subsequent solution casting. Transmission electron microscopy and small-angle X-ray scattering data showed that at low silica content ultra-small silica particles with a size smaller than the diameter of the ionic channels were homogeneously dispersed in the PFSA matrix. Such morphology leads to enhanced proton mobility as probed by impedance spectroscopy and 1H solid-state NMR, and eventually resulted in the improvement of fuel cell performance.
Keywords :
Polymer electrolyte membrane fuel cells , proton exchange membrane , Perfluorosulfonic acid , silica , Polyethoxysiloxane , Sol–gel process
