A Critical Review on Mesoporous Photoanodes for Dye-Sensitized Solar Cells

Until breakthrough in 1991, commercialization of dye-sensitized solar cell (DSSC) has been a gradual process leading to a scarce production. A thorough study of dilemmas is needed to overcome the shortcomings of DSSC to make it stand against traditional silicon based solar cells. A DSSC is composed of important components including photoanode, dye, electrolyte and counter electrode. Among these photoanode is the focussed area of the presented article. The photoanode is a thin porous film of metal oxide semiconductor supported on to a transparent conducting oxide (TCO) glass. Extensive research in this field has revealed the photophysics of semiconducting electrodes like TiO2, ZnO and SnO2 etc. Selection of metal oxide for this purpose relies on crystallinity, particle size, and thickness of the film, surface area, dye affinity and porosity. These parameters related to the candidature of a particular metal oxide film as photoanode in DSSC have been discussed and optimized values have been quoted. The present study aims at emphasizing the history of DSSC as well as recent developments in electrodes, dyes and electrolytes in this specific area.