Triphenylamine derivatives : synthesis, electrochemical, photophysical properties and DFT studies

Abstract

In recent years a lot of work has been done in the field of dye-sensitized solar cells (DSSC). Dye-sensitized solar cell is a cost efficient way for light-energy conversion. Triphenylamine based organic dyes (with D–p–A structure) as sensitizer for dye-sensitized solar cells (DSSCs) attain considerable attention because of their structural versatility, low cost and high molar absorption coefficient. Two triphenylamine derivatives are synthesized by Sonogashira cross-coupling. Their electronics, photonics and computational studies reveal strong donor–acceptor interaction. The starting material 4,4'-((4-ethynylphenyl)azanediyl)dibenzaldehyde was synthesized by Sonogashira coupling reaction. The absorption spectra of the triphenylamine-derivatives were recorded in DMSO. The UV-visible absorption spectra were in the range of 380-480 nm. The electrochemical studies shows one oxidation peak corresponding to the oxidation of triphenylamine unit. The thermal stability of the Triphenylamine derivatives are reported, in which the melononitrile adduct show high thermal stability. The DFT calculation reveals the distribution of HOMOs over triphenylamine moieties with LUMOs over aldehyde and cyano moieties.