Energy production using dye-sensitized solar cells by TiO2 nanoparticles fabricated with several natural dyes

The present work displays the use of natural dyes extracted from native plants as sensitizer for fabrication of dye-sensitized solar cells (DSSCs). The native plants named as comellia sinensis, punica granatum L. var sativa k.maly, morus nigra, rubia tinctorum and brassica oleracea were collected from Kashan area, Iran. The extracted dyes were characterized with the aid of UV–Vis and Fourier transform infrared (FT-IR) spectroscopies. The FT-IR results revealed the presence of hydroxyl groups in the chemical structures of the natural dyes, improving the interaction of between photosensitizer and TiO2 surface in solar cell devices. In addition, photoelectrochemical performance of the DSSCs based on the natural dyes illustrated short-circuit photocurrent (Jsc) and open-circuit voltages (Voc) ranging from 0.5 to 2.36 mA/cm2 and 0.38 to 0.62 V, respectively. Since cyanidin- glucoside compounds were the main pigment of brassica oleracea, interaction between plenty of hydroxyl groups of these compounds and TiO2 surface was very efficient, this sensitizer owned the best photovoltaic performance among all the natural dyes.