Betalain and anthocyanin dye-sensitized solar cells

• Published in: Journal of applied electrochemistry 2016-09, Vol.46 (9), p.929-941
• Main Authors: Ramamoorthy, Raja, Radha, Natarajan, Maheswari, Govindaraj, Anandan, Sambandam, Manoharan, Subbaiah, Victor Williams, Rayar
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Electrochemistry; Industrial Chemistry/Chemical Engineering; Physical Chemistry; Research Article; Solar Cells
• ISSN: 0021-891X; 1572-8838
• DOI: 10.1007/s10800-016-0974-9

In the present work, the mechanism behind the functioning of the eco-friendly dye-sensitized solar cell was explored. Dye-sensitized solar cells were fabricated using natural dyes extracted from common pear ( Opuntia dillenii ) and red tamarind ( Tamarindus indica ), and 1:1 mixture. Betalain and anthocyanin were identified as the main pigments that sensitize the semiconductor TiO 2 film. The best conversion efficiency of 0.47 % was achieved from betalain dyes and 0.14 % from anthocyanin dye-sensitized solar cell [under standard Air Mass 1.5 illumination (85 mW cm −2 )]. The mixture of dye (1:1 mixture) adsorbed onto TiO 2 exhibited an efficiency of 0.20 %. The light absorption behavior of extracted dyes was studied using ultraviolet–visible analysis. The influence of the binding nature of the dyes with TiO 2 surface on the efficiency of the solar cells was analyzed through Fourier transform infra-red analysis. The electrochemical impedance spectroscopy was used to find out the internal charge transfer resistance of the cells. The device incident photon-to-current efficiency was obtained from 5 to 25 % for different natural dyes and found to coincide with the photocurrent–voltage characteristics and electrochemical impedance spectroscopy analysis. Graphical Abstract