Spectroscopic and electrochemical behavior of newly synthesized high fluorescent symmetric 4′-nitrophenyl-3,4,9,10-perylenebisdiimide-azo hybrid dyes

•1,6,7,12-Teraazophenoxy perylene bis diimide azo hybrid dyes have been synthesized.•Synthesized dyes are thermally as well as photochemically stable.•Synthesized dyes are highly luminescent.

The investigation has been made in the synthesis of azo hybrid rylene dyes. The hybridization of perylene bis-diimide with phenolic azo-dyes was carried out by the nucleophilic substitution (SNAr) reaction of tetrachloroperylene-3,4,9,10-bisdiimide 3 with phenolic azo-dyes 4a–g in basic medium. The hybrid dyes exhibited two absorption maxima λmax in the range 300–350, 426–438 nm in ethanol due to presence of azo linkage and highly conjugated framework of π bonds. Fluorescence spectra of these dyes in water showed sharp emission peaks with small bandwidths in the range 490–495 nm, and fluorescence quantum yield was 0.71–0.83 in comparison with standard reference fluorescein. The structures of perylene-azo dyes were elucidated by FTIR and NMR spectroscopy. Luminescence was determined by LS-100 meter which was found to be excellent in limits 0.208–0.239 cd/m2. Cyclic voltammetric studies were made by Electrochemical Analyzer CH1830C which showed the oxidation chemical potential of these hybrid dyes.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide