Influence of saffron carotenoids and mulberry anthocyanins as natural sensitizers on performance of dye-sensitized solar cells

Abstract

This study reports the effect of saffron carotenoids and mulberry anthocyanins as natural sensitizers on electron transfer process and performance of dye-sensitized solar cells (DSSCs). A simple extraction method was used for separation of stable pigments containing anthocyanins from black mulberry and carotenoids from saffron and used in fabrication of DSSCs. Photovoltaic performance of fabricated DSSCs were measured and the results compared. A conversion efficiency of 0.29 % (Jsc 0.9 mA cm−2, Voc 0.45 v, fill factor 0.72) was obtained under sun (Am1.5) in the case of natural dye extracted from black mulberry. Furthermore, in order to measure electron transport behavior and electron density in the conduction band of TiO2 (ns), the electrochemical impedance spectroscopy was employed. According to the existence of more effective functional groups on anthocyanins extracted from black mulberry, the higher density in the conduction band (5.6 × 1017) and lower electron transport resistance (40 Ω) was obtained compared to the carotenoids extracted from saffron.