Utilization of electron-deficient thiadiazole derivatives as π-spacer for the red shifting of absorption maxima of diarylamine-fluorene based dyes

This study is carried out to design diarylaminefluorene dyes by incorporating electron-deficient thiadiazole derivatives. Quantum chemical calculations are performed to study the geometries, electronic structures and absorption spectra of the dyes. Interaction of dyes with TiO2 cluster is also studied. The effects of the electron-deficient units on the spectra and electrochemical properties have been investigated. Dyes D1-D4 display remarkably enhanced spectral response in the red portion of the solar spectrum as compared with reference compound D0. The newly designed dyes demonstrate desirable energetic and spectroscopic parameters and may lead to efficient metal-free organic dye sensitizers for DSSCs.