Incorporation of Kojic Acid-Azo Dyes on TiO₂ Thin Films for Dye Sensitized Solar Cells Applications

Sensitization of heavy metal free organic dyes onto TiO 2 thin films has gained much attention in dye sensitized solar cells (DSSCs). A series of new kojic acid based organic dyes KA1–4 were synthesized via nucleophilic substitution of azobenzene bearing different vinyl chains A1–4 with kojyl chloride 4 . Azo dyes KA1–4 were characterized for photophysical properties employing absorption spectrometry and photovoltaic characteristic in TiO 2 thin film. The presence of vinyl chain in A1–4 improved the photovoltaic performance from 0.20 to 0.60%. The introduction of kojic acid obtained from sago waste further increases the efficiency to 0.82–1.54%. Based on photovoltaic performance, KA4 achieved the highest solar to electrical energy conversion efficiency (η = 1.54%) in the series.