Improvement of dye-sensitized solar cell performance through electrodepositing a close-packed TiO2 film

A simple electrodepositing method was proposed for fabricating a uniform, tight, and close-packed TiO(2) nanocrystalline film on the ITO substrate. The electrode and dye-sensitized solar cell (DSSC) with electrodeposited TiO(2) layer were characterized by scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The phthalocyanin dye, zinc tetra-carboxyl phthalocyanin complex, was used as a model dye to evaluate the influence of close-packed TiO(2) blocking layer on the photocurrent-voltage property. On the electrodeposition, the close-packed TiO(2) layer could effectively inhibit the recombination of charges, and therefore improve the performances of the corresponding cells. The effects of film thickness on light transmittance and photocurrent density of the corresponding cell were also demonstrated. The optimum film thickness was found to be approximately 400 nm. At the optimum thickness, the photocurrent density greatly increased comparing with that of the screen printing TiO(2) film. These results imply that our proposition was a potential and feasible method for the fabrication of DSSC practically.