Cocktail dyes from blueberry and dragon fruit in the application for DSSC

This paper optically characterized anthocyanins and betalains pigments in blueberry and dragon fruit, respectively, to function as a dye sensitizer in dye-sensitized solar cell (DSSC).Ultrasonic extraction treatment was enforced to cocktail dye with a temperature, time and frequency rating of 30 °C, 30 minutes and 37 Hz, respectively. Different extracting solvent from ethanol and distilled water were used to observe the absorption spectra by using UV-Vis absorption spectroscopy. Fourier transforms infrared (FT-IR) were used to characterize the functional components of dyes. From FT-IR spectra, cocktail dye represented the existing of carboxyl group correspond to the CO=OH stretching vibrations which is an important functional group in betalains pigment. From UV-Vis absorption spectra, the cocktail dye extracted with ethanol (M-Etha), compared to DI-water (M-DI) has the peak absorbance of 500 nm with broader absorbing range in visible light spectrum (450-600 nm). As for the photon energy, results show a narrow energy gap of 2.49 eV with higher absorption coefficient of 2.17 km^-1.