Studies on PV assisted PEC solar cells for hydrogen production through photoelectrolysis of water

We report the formation of polycrystalline TiO2 film (rutile phase; tetragonal: a = 4.593 Angstrom and c = 2,959 Angstrom) by anodic oxidation of titanium sheet. The microstructural characterization revealed the porous nature of the film consisting of randomly oriented microcrystals. The photoelectrochemical (PEC) characterization of TiO2, films has been carried out by employing standard electrochemical techniques. The investigations being reported involve I-V and C-V measurements, besides the use of PEC cell for hydrogen production by employing photovoltaic power as external biasing source. The open circuit voltage and short circuit current for the cell were found to be 780 mV and 9.27 mA cm(-2), respectively. The observed frequency dispersion in Mott-Schottky plots was related to the presence of interface states participating in the charge exchange with bulk electrolyte. The hydrogen production rates were found to be 37.4 and 24.61 h(-1) m(-2), respectively, for PV biased PEC and PV (stand-alone) driven electrolysis modes. (C) 2001 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.