Natural dyes as sensitizers for dye-sensitized solar cells

The dye-sensitized solar cells (DSSCs) have been fabricated by using a series of natural dyes extracted from euonymus japonicus and purple plants. The optical characteristics and chemical structure of dyes were investigated by UV-visible spectroscopy and Fourier infrared spectroscopy. It is found that the absorption of sunlight and bonding performance to TiO2 electrode of dyes had significantly effects on the conversion efficiency of solar cells. The results show the cells using blueberry as sensitizer achieved best conversion efficiency of 0.218%, attributed to its strong absorption and excellent bonding to the TiO2 electrode, correspondingly, the short-circuit photocurrent density (Jsc) and open-circuit voltage (Voc) were 1.3mA/cm2 and 430mV, respectively.