Advances in anodic alumina membranes thin film fuel cell: CsH2PO4 pore-filler as proton conductor at room temperature

Anodic alumina membranes (AAM) filled with cesium hydrogen phosphate proton conductor have been tested as inorganic composite electrolyte for hydrogen-oxygen thin film (<= 50 mu m)fuel cell (TFFC)working at low temperatures (25 degrees C), low humidity (T-gas = 25 degrees C) and low Pt loading (1 mg cm(-2)). Single module TFFC delivering a peak power of around 15-27 mW cm(-2). with open circuit voltage (OCV) of about 0.9 V and short circuit current density in the range 80-160 mA cm(-2) have been fabricated. At variance with pure solid acid electrolytes showing reproducibility problems due to the scarce mechanical resistance,the presence of porous alumina support allowed to replicate similar fuel cell performances over numerous AAM/CsH2PO4 assemblies. A scale-tip process of the electrodic area has been optimized in order to increase the delivered peak power of AAM thin film fuel cell. Morphological, chemical and electrochemical studies on the alumina composite electrolyte have been carried out by means of scanning electron microscopy, Xray diffractometry, Micro-Raman spectroscopy, DTA/DTG analysis, ac impedance spectroscopy and single fuel cell tests. (c) 2008 Elsevier B.V. All rights reserved.