Investigation on tio2 nanostructures sensitized using kigelia africana and hibiscus sabdariffa for dye sensitized solar cells

Abstract

Dye-Sensitized Solar Cell DSSC as compared to conventional photovoltaics draws considerable attention to meet future solar energy market because of its simple preparation procedure environmental compatibility and reasonable performance Moreover DSSC differ from conventional photovoltaic cells by its independent process of light absorption and charge transport phenomena DSSCs are based on the sensitization of mesoporous metal oxide films generally TiO2 using suitable dyes and excitation of sensitized molecules by absorption of visible light The most successful dyes/sensitizers with good stability and yielding high efficiency are based on ruthenium Ru bipyridyl compounds Even though Ru based dyes are capable of yielding conversion efficiencies greater than 13 they suffer from several limitations such as higher cost tendency to undergo degradation usage of toxic materials and involves multi step preparation procedures These limitations have forced researchers to look for alternatives that are biocompatible easily available non-toxic and cheaper One such alternative is the use of natural sensitizers that can be easily extracted from natural products like fruits flowers leaves seeds barks etc and can be employed in DSSC Natural dyes extracted from these products contain anthocyanins betalins chlorophylls etc Among them anthocyanins are widely present in most of the flowers and fruits and are responsible for their characteristic red and blue colors. newline