Hybrid Membranes Based in Nafion-metallic Oxides: Performance Evaluations

Abstract

Proton exchange membrane fuel cells (PEMFCs) are a class of low temperature fuel cells characterized by a high energy density, good compatibility with the environment and a wide variety of applications. In this work, four hybrid membranes organic-inorganic based on Nafion [Nafion-TiO2, Nafion-ZrO2, Nafion-(TiO2-ZrO2) and Nafion-YSZ] have been fabricated and evaluated in order to be used as electrolytes in intermediate temperature proton exchange membrane fuel cells (IT-PEMFCs). Doctor Blade technique has been the method used to fabricate these membranes since it simplifies the synthesis and scale-up of hybrid films. Thereby, very homogeneous nanocomposite membranes with high reproducibility, low thicknesses and large size have been easily obtained. The hybrid membranes have been evaluated in terms of water uptake and further characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Finally, the hybrid membranes were used in the fabrication of membrane-electrode assemblies (MEAs), placed in single cells, and tested in operating conditions. In this study the method for films preparation has been improved and the presented results allowed to identify the membranes with the best performance and potential applicability as electrolytes in IT-PEMFCs.