Efficiency Improvement of Dye-sensitized Solar Cells by Phosphor (Y2O3:Er3+, Y3Al5O12:Ce3+) Co-doped TiO2 Electrodes

Abstract

Generally, the (N-719) dye used in dye-sensitized solar cells (DSSCs) only absorbs visible light in the wavelength range from 400 to 700 nm. Most of the ultraviolet and infrared rays from the sun are not utilized by this dye. However, ultraviolet and infrared rays can be converted to visible light by upconversion luminescence. Such visible light can then be reabsorbed by the dye, allowing for a greater range of solar irradiation to be utilized in DSSCs. A mixed phosphor of Y3Al5O12:Ce3+ and Y2O3:Er3+, acting as luminescence medium, was added to the TiO2 electrode of DSSCs, increasing the photocurrent density and efficiency as a result of the upconversion. The Y3Al5O12:Ce3+/Y2O3:Er3+ phosphor-co-doped TiO2 electrode cells showed better performance than the phosphor-free cells. In this paper, we describe the characterization of DSSCs containing the mixed Y3Al5O12:Ce3+/Y2O3:Er3+ phosphor and discuss the enhanced efficiencies of the DSSCs as compared with those of phosphor-free cells.