Synthesis and characterization of 5,7-dimethyl-8-hydroxyquinoline and 2-(2-pyridyl)benzimidazole complexes of zinc(II) for optoelectronic application

Bis(5,7-dimethyl-8-hydroxyquinolinato)zinc(II) (Me2q)2Zn and 5,7-dimethyl-8-hydroxyquinolinato(2-(2-pyridyl)benzimidazole) zinc(II) Me2q(pbi)Zn have been synthesized and characterized by various techniques. These metal complexes have high thermal stability (>300 °C) and high glass transition temperatures (>150 °C). The vacuum deposited films of these materials show good film forming property and are suitable for opto-electronic applications. Multilayered organic electroluminescent (EL) devices have been fabricated having structure ITO/α-NPD/zinc complex/BCP/Alq3/LiF/Al, which produce emission with chromaticity having Commission Internationale d’Eclairage (CIE) coordinates x = 0.506 and y = 0.484 for (Me2q)2Zn; x = 0.47 and y = 0.52 for (Me2q)(pbi)Zn complex. The electroluminescence spectra show peak emission centered at 572 and 561 nm respectively for these materials.

Graphical AbstractFigure optionsDownload high-quality image (48 K)Download as PowerPoint slideHighlights
► Two zinc complexes have been synthesized and characterized.
► Synthesized complexes have high thermal stability and high glass transition temperatures.
► The vacuum deposited films of these materials shows good film forming property.
► The excitons were formed at the Zn complexes and are used as emissive materials.
► The chromaticity of the devices was found to be independent of the operating voltage.