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

Carolynne Zie Wei Sie,Zainab Ngaini

doi:10.1155/2017/2760301

Abstract

Sensitization of heavy metal free organic dyes onto TiO2 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 TiO2 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.

Highlights

Dye sensitized solar cells (DSSCs), a third-generation solar cell discovered in early 1990s, have gained intensive attention and been considered as promising alternative for fossil fuel energy [1, 2]
We report on the synthesis of heavy metal free photosensitizer of organic dye azobenzene, which consists of vinyl chain as spacer and kojic acid anchoring group for DSSCs application
Low yield obtained was due to the properties of kojic acid which is soluble in both water and ethyl acetate [34, 35]

Summary

Introduction

Dye sensitized solar cells (DSSCs), a third-generation solar cell discovered in early 1990s, have gained intensive attention and been considered as promising alternative for fossil fuel energy [1, 2]. DSSCs offer advantages over the conventional silicon based solar cell due to cost effectiveness, flexibility in shape, easy accessibility of dye resources, and noteworthy performance [3, 4]. Tremendous efforts have been made to explore natural and organic dye as DSSCs sensitizer due to being nontoxic and environmentally friendly, low cost, and easy modification for functionalization. Extracted natural dye has low yields of extract and scarce resources [10]. Organic dye such as azobenzene has outstanding chromophores with strong absorption in visible region and intrinsic advantages of good photo and thermal stability [11, 12]. Azobenzene is a reactive precursor for functional group conversion and attachment such as vinyl and alkoxy chain with enhanced optical properties [13, 14]

Methods

Results

Conclusion