Enhanced Photoelectric Conversion of Dye-sensitized Solar Cell by Addition of Inorganic Particles

"Electrochemical impedance spectroscopy and cyclic voltammetry were used to investigate the effect of various inorganic particles, including titania, alumina, zirconia with particle sizes ranging from nano- to micro-meter on electrochemical properties of the electrolyte used in dye-sensitized solar cell. Adding inorganic particles could improve the ionic transport of I3- in the electrolyte and reduce the electrolyte-electrode transfer resistance, leading to an improvement of the photoelectric conversion efficiency of the devices. It was proposed that the improvement could be attributed to the interfacial effect between the inorganic particles and the electrolyte; ionic conduction paths formed between the solid particles facilitate the diffusion of the I3- in the electrolyte and improve the connection between the electrolyte and the electrode. Combined with a less volatile solvent system and a proper amount of the inorganic particles as the additive, an overall efficiencyof 5.5% for the DSC (1 cm2) with P25 (10%) under 100 mW/cm2 at room temperature was achieved, an improvement of 51% over that without the oxide additive."