Preparation And Characterization Of Core-shell Electrodes For Application In Gel Electrolyte-based Dye-sensitized Solar Cells

Core-shell electrodes based on TiO2 covered with different oxides were prepared and characterized. These electrodes were applied in gel electrolyte-based dye-sensitized solar cells (DSSC). The TiO2 electrodes were prepared from TiO2 powder (P25 Degussa) and coated with thin layers of Al2O3, MgO, Nb2O5, and SrTiO3 prepared by the sol-gel method. The core-shell electrodes were characterized by X-ray diffraction, scanning electron microscopy and atomic force microscopy measurements. J-V curves in the dark and under standard AM 1.5 conditions and photovoltage decay measurements under open-circuit conditions were carried out in order to evaluate the influence of the oxide layer on the charge recombination dynamics and on the device's performance. The results indicated an improvement in the conversion efficiency as a result of an increase in the open circuit voltage. 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