The Effects of the Concentration of Red and Yellow Gambier Fruit Dyes on the Short-Circuit Photocurrent in Dye-Sensitised Solar Cells

Abstract

Natural dyes still have low efficiency, although there are good opportunities to apply them in dye-sensitised solar cells (DSSCs). In this research, the working-electrode was prepared from indium tin oxide (ITO) and titanium oxide (TiO2), using the doctor blade method for doping TiO2 on ITO glass. Then, the working-electrode was soaked in gambier extract for 24 hours. The counter-electrode and electrolyte were made from burning a candle and mixing KI + I2, respectively. UV-vis and FTIR spectra have been made to investigate the effect of the concentration of red and yellow gambier prepared by maceration and evaporation from methanol. They were used to analyse absorbances and compounds in gambier, respectively. From UV-vis and FTIR spectra results, we obtained that the organic dyes from the red and yellow gambier fruits could have a high potential to be used as a sensitiser to absorb photons in DSSCs. From the I–V measurement, we found that the efficiency tends to increase as the concentration increases. It indicates that the concentration of natural dyes could increase the performance of DSSC. Furthermore, an efficiency of 3.248% was found to be achievable for DSSCs from a 70% concentration of yellow gambier fruit dye.