DFT and TD-DFT Investigations of Diazensulfonate Dye Sensitizers for Solar Cells: Effects of Hydroxyphenyl, Methoxyphenyl and Methylthiophenyl Substitution on the Dye

Solar energy is the greatest source for production renewable energy carriers on the earth. Organic and inorganic dyes anchored to semiconductor nanoparticles, have been found important applications as photosensitizes for solar cells and other optoelectronic systems. In this study, the influence of hydroxyphenyl, methoxyphenyl and methylthiophenyl substitution on the (E)-2-(2-hydroxyphenyl) diazenesulfonate dye were investigated. Calculations were done using software Gaussian 98. Dye molecules were optimized by DFT/6-31G (d, p) method in gas phase. Dyes were optimized in Chloroform, Ethanol and THF solvents by using CPCM model and DFT/6-31G (d, p) method. Different functional groups effects were studied in the ability of diazensulfonate dye to absorption sunlight. According to the results of our computational, methoxyphenyl substitution in Ethanol solvent, red shift is caused.