Organic/inorganic nanocomposite gels employed as electrolyte supports in Dye-sensitized Photoelectrochemical cells

Abstract

Dye-sensitized photoelectrochemical cells based on TiO2 mesoporous films, a ruthenium bipyridyl derivative as photosensitizer and a SiO2/poly(ethylene glycol)-200 nanocomposite thin film as electrolyte support, have been constructed. TiO2 films have been deposited on conductive transparent Indium-Tin Oxide glass slides by means of a sol-gel procedure carried out in reverse-micellar solutions. The photosensitizer has been adsorbed on titania films from ethanolic solutions while the electrolyte layer has been synthesized by a sol-gel procedure. The presence of silica in the nanocomposite electrolyte gel provides the gelifying agent, the compound that holds the cell together in a sandwich form and the sealing agent that protects the cell and secures its long-term function. PEG-200 makes the organic subphase which provides the ionic conductivity. The present work describes the construction of the cell and the study of its efficiency. A variant of the cell has also been made by incorporating Ag+ and Ru3+ ions into titania particles, but these dopants did not improve cell efficiency, either in their oxidized or in their reduced form.