The Development of Highly Fluorescent Hemicyanine and Dicyanoisophorone Dyes for Applications in Dye-Sensitized Solar Cells

Ruthenium-based metal complex dyes have been employed extensively in dye-sensitized solar cells (DSSCs) as photosensitizers, but the cost and toxicity of metal complexes have promoted the development of metal-free organic dyes. The present investigation deals with the synthesis of hemicyanine and Dicyanoisophorone (DCI) based dyes adopting the D-pi-A strategy, and their application on sensitization of nano-crystalline ZnO electrodes by appending the carboxyl (COOH) anchoring group as a pendant on the primary skeleton of dyes. Dyes have been characterized by UV, FTIR, and NMR spectroscopic studies. Absorption maxima (lambda(max)) were found in the region 416-551 nm while emission wavelength (lambda(em)) was observed in the range 575-685 nm. Cyclic voltammetry and DFT calculations were used to estimate redox potential and band gap energies of dyes.

Automated summary

This study focuses on the synthesis of hemicyanine and Dicyanoisophorone (DCI) based dyes using the D-pi-A strategy, and their successful application in sensitizing nano-crystalline ZnO electrodes. The dyes were characterized by UV, FTIR, and NMR spectroscopic studies, with absorption maxima in the range of 416-551 nm and emission wavelength in the range of 575-685 nm. Cyclic voltammetry and DFT calculations were used to estimate the redox potential and band gap energies of the dyes.