Characterization of eosin red and hibiscus sabdariffa-based dye-sensitized solar cells

Abstract

The fabrication of dye-sensitized solar cell (DSSC) using Eosin red and Hibiscus sabdariffa has been conducted in this study. Eosin red and Hibiscus sabdariffa dyes were used as photosensitizers. The dyes were prepared by dissolving 1 g each of Eosin red and Hibiscus sabdariffa in 30 ml of isopropyl alcohol (IPA) solution. A semiconductor TiO2 paste was deposited on FTO glass using doctor blade technique and its films were dipped in the dye solutions for 10 h. This DSSC consists of working electrode and counter electrode sandwiched together. The TiO2 powder used was identified using X-Ray diffractometer. The optical and functional groups of the dyes were characterized using UV–Visible Spectrophotometer and FTIR Spectrometer respectively. The electrical characterization was carried out using solar simulator under AM 1.5 and Keithley Multimeter. The results of the current-voltage measurements of Eosin red-based DSSC had short circuit current of 0.035 mA and an open circuit voltage of 0.34 V with maximum current of 0.025 mA and a maximum voltage (Vmax) of 0.20 V. Hibiscus Sabdariffa-based DSSC has short circuit current (Jsc) of 0.075 mA and an open circuit voltage (Voc) of 0.38 V with maximum current (Imax) of 0.06 mA and Vmax of 0.20 V. The efficiencies of the two cells were estimated to be 1×10−6 % and 5×10−7 % for Hibiscus sabdariffa and Eosin red-based DSSCs respectively. This supports that natural sensitizer that is available; ecofriendly and affordable can favorably replace the synthetic dye under good conditions.