Efficiency Enhancement of Cocktail Dye of Ixora coccinea and Tradescantia spathacea in DSSC.

Zularif Zolkepli,Piyasiri Ekanayake,Kushan Tennakoon,Andery Lim

doi:10.1155/2015/582091

Abstract

The use of anthocyanin dyes extracted from epidermal leaves of Tradescantia spathacea (Trant) and petals of Ixora coccinea (IX) was evaluated in the application of dye-sensitized solar cells (DSSCs). Subsequently, cocktail anthocyanin dyes from these dyes were prepared and how they enhanced the cell's overall performance was assessed using five different volume-to-volume ratios. Cocktail dyes absorbed a wider range of light in the visible region, thus increasing the cell efficiencies of the cocktail dyes when compared to the DSSC sensitized by individual dyes. The surface charge (zeta-potential), average size of aggregated anthocyanin molecules (zetasizer), and anthocyanin stability in different storage temperatures were analyzed and recorded. Lower size of aggregated dye molecules as revealed from the cocktail dyes ensured better adsorption onto the TiO2 film. Tradescantia/Ixora pigments mixed in 1 : 4 ratio showed the highest cell efficiency of η = 0.80%, under the irradiance of 100 mW cm−2, with a short-circuit current density 4.185 mA/cm2, open-circuit voltage of 0.346 V, and fill factor of 0.499. It was found that the desired storage temperature for these cocktail dyes to be stable over time was −20°C, in which the anthocyanin half-life was about approximately 1727 days.

Highlights

Dye-sensitized solar cell (DSSC) is a photovoltaic technology developed by O’Regan and Gratzel in 1991 [1], known as Gratzel cell
This paper describes the use of these two natural anthocyanin dyes from both plants as cocktail dye in DSSC
Five cocktail mixtures of dyes extracted from Ixora coccinea (IX) flower petals and Tradescantia spathacea (Trant) lower epidermal peels were assessed as potential candidates to increase the efficiency in DSSCs

Summary

Introduction

Dye-sensitized solar cell (DSSC) is a photovoltaic technology developed by O’Regan and Gratzel in 1991 [1], known as Gratzel cell. Anthocyanins are natural components that are responsible for the red-purple color of fruits, flowers, and leaves of plants. They may present in other plant tissues such as roots, tubers, and stems [2, 3]. They absorb light in the range of 520–550 nm wavelength [10] and are pH dependent, usually red in color in an acidic medium but turning into blue in less acidic condition [6]. The effect of different volume-to-volume ratio concentrations on the photoelectric conversion efficiency of dye-sensitized solar cells is determined

Experimental Section

Results and Discussion

Conclusions