Nanoporous alumina membranes filled with solid acid for thin film fuel cells at intermediate temperatures

Thin film fuel cells have been fabricated by impregnation of inorganic porous membranes with inorganic proton conductor. Anodic alumina membranes (50 mum thick and pore diameter of 200 nm), filled with CsHSO4 salt have been used as protonic conductor in a hydrogen-oxygen fuel cell working between 423 and 443 K in dry atmosphere. Polarization curves at 433 K showing ohmic control with open circuit values near 0.8 V and short circuit current around 8 mA cm(-2) have been obtained. Possible causes of degradation as well as alternative routes to overcome some of the problems encountered with this approach will be reported. (C) 2004 Elsevier B.V. All rights reserved.