The H-2/O-2, fuel cell based on the proton conducting P2O5-ZrO2-SiO2 glasses was prepared by sol-gel technique. Structural characterization were carried out using X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance ((31)p MAS NMR), N-2 adsorption-desorption analysis, differential thermal analysis (DTA) and thermal gravimetric analysis (TGA) and impedance measurements. The absorption bonds of Si-O-Si, Si-O-P and Si-O-Zr were observed in the P2O5-ZrO2-SiO2 glasses which were heat treated at 600 degrees C. A sample (5P(2)O(5)-4ZrO(2)-91SiO(2), mol%) was selected as the electrolyte for the H-2/O-2 fuel cell test and yielded the maximum power density value of 8.5 mW/cm(2) using electrochemical measurements at 30 degrees C under relative humidity atmosphere. (c) 2005 Elsevier Ltd. All rights reserved.