New Types of Dye-Sensitized Solar Cells Based on Natural Dyes

A new type of dye sensitized solar cells was constructed, many different parameters were investigated to enhance their efficiencies. Two types of titanium dioxide powders were used to prepare the TiO2 thin film electrode for the cell. Anatase and rutile titanium dioxide thin film electrodes were prepared by the Dr. Blade technique. Anatase thin films were proved to give better results than rutile films under similar conditions, with a conversion efficiency of 0.22% and a fill factor of ~ 60%. The solar cells were sensitized using two natural dyes, curcumine and anthocyanin (which was extracted from three sources; red cabbage, beets and roselle). Curcumine sensitized solar cells gave better conversion efficiencies than all three types of anthocyanins. The PEC measurements were performed using three different types of electrolyte solutions: Iron, sulfur and iodine. Iodine electrolyte gave the best results for both solar cells sensitized with anthocyanin and with solar cells sensitized with curcumine. The effect of changing the pH value of the iodine electrolyte solution was also investigated; higher conversion efficiency was obtained using basic electrolyte solution. The effect of TiO2 layer thickness on PEC characteristics was also studied (130 µm and 150 µm). The 150 µm thin films gave better results for both anatase and rutile electrodes.