Polycrystalline CdTe thin films were prepared by electrodeposition from an aqueous solution containing 1.5 M CdSO(4) and 100-200 mum HTeO(2)(+). The films were characterized by X-ray diffraction to evaluate the structure. Photoelectrochemical investigation has been carried out using the electrode/electrolyte configuration n- or p-CdTe/Nafion electrolyte. The Mott-Schottky plots were drawn using the space-charge capacitance data at 1 kHz frequency. From the C-V analysis the flat band potential and the carrier concentration were calculated. Preliminary results indicate that p-CdTe/Nafion combination may lead to a new design strategy for the photoclectrochemical/fuel cell hybrid system for the onboard production and utilization of hydrogen. (C) 2002 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.