Effect of donor groups on organic and ZN porphyrin dyes as sensitizers in dye sensitized solar cells

Abstract

Many researchers are involved to develop the third generation solar cell Dye-Sensitized Solar Cells DSSCs have attracted great interest due to environmental friendliness easy fabrication low cost and high power conversion efficiency DSSC consists of four major components such as semiconductor dye (sensitizer) electrolyte and counter electrode Among the four components the sensitizer plays a crucial role to the generation of electrons At present ruthenium complex dyes are widely used in DSSC However it is expensive and rare earth material This affects the large scale production In order to develop cost effective DSSC Ruthenium free and earth abundant materials have been developed Organic dyes and Zn-Porphyrin derivatives have variety of advantages such as easily available precursor materials simple synthesis steps low cost high molar extinction coefficients and good electrochemical properties The synthesis and fabrication of various organic dyes and Zn-Porphyrin derivatives have stimulated great interest in developing low cost and efficient ruthenium free sensitizer materials for DSSC The first chapter gives an introduction of solar cells and their classifications including brief introduction of DSSC working principle of DSSC components of DSSC like photoanode electrolyte counter electrode and sensitizers Moreover classifications of sensitizers and common features of sensitizers are given The second chapter deals with synthesis of 2-cyano-3-(4-dimethylaminophenyl)prop-2-enoic acid by the condensation of 4- dimehylaminobenzaldehyde and methyl-2-cyanoacetate followed by purification with column chromatography The structure of the dye molecule is confirmed by 1H Nuclear Magnetic Resonance (1H NMR) and 13C Nuclear Magnetic Resonance (13C NMR) spectrum Fourier Transform Infrared (FTIR) spectrum revealed the functional groups of the dye molecule The electronic properties of the molecules were analyzed by Ultraviolet Visible absorption spectroscopy