PREPARATION AND CHARACTERIZATION OF NOVEL PROTON CONDUCTING MEMBRANES FOR THIN FILM FUEL CELL

This paper reports on the preliminary results concerning the possible functioning of novel composite membranes based on Porous Anodic Alumina in a H₂/O₂ fuel cell. The Anodic Alumina Membranes (AAM) supports are suitable for applications in miniaturized or thin film fuel cells. In fact they offers the possibility to reduce the fuel cell structure to micrometer sizes, thanks to the micromachining technology.
The thin film fuel cells have been fabricated by impregnation of anodic porous alumina membranes (AAM) with Cesium Hydrogen Sulphate, Nafion^® and Phosphotungstic acid (PWA).
Porous alumina supports (50 µm thick and pore diameter of 200 nm) were filled with the proton conductor and characterized by means of Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and thermal analysis (DTA).
The electrochemical characterization of impregnated AAM was carried out by recording the polarization curves of a hydrogen-oxygen fuel cell working at intermediate temperatures (160 °C) for AAM/CsHSO₄ membranes and at low temperatures (25÷80 °C) in humid atmosphere for AAM/PWA and AAM/ Nafion^® membranes.