Natural Dye Extracted From Saraca asoca Flowers as Sensitizer for TiO2 Based Dye Sensitized Solar Cell

Abstract

In this work, we have chosen the low cost natural dye extracted from Saraca asoca flowers to act as a sensitizer dye for TiO2based dyesensitized solar cell (DSSC). UV–visible spectroscopic studies of ethanolic extract of dyes have been done in order to understand light absorption behavior of dye. The natural dye extract covers appreciable spectrum of solar radiation, 400–500 nm with an absorption maximum at 450 nm that makes it suitable for use as a photosensitizer in DSSC application. The dye adsorbed onto the semiconductor facilitates electron transfer across the dye/semiconductor interface. FTIR spectra of extract revealed the presence of anchoring groups and coloring constituents. DSSC fabricated with TiO2 and natural dye extract obtained from Saraca asoca flowers as sensitizer has shown opencircuit voltage (Voc) 516 mV, shortcircuit current density (Jsc) 0.29 mA/cm2, fill factor (FF) 0.65, incident photontocurrent conversion efficiency (IPCE) 43%, and conversion efficiency of 0.09%. This work briefly discusses the simple extraction technique of natural dye and its performance in DSSC.