Design, Synthesis and Characterization of N-Substituted Heteroaromatics: DFT-Studies and Organic Light Emitting Device Application

Abstract

Schiff's base condensation of 4,5-Dimethyl-1,2-phenylenediamine with various aldehydes namely fluorene-2-carboxaldehyde (MBF), N-ethyl-3-carboxaldehyde (MBE), 8-hydroxyjulolidine-9-carboxaldehyde (MBJ) and N-(4-formylphenyl) carbazole (MBB) functioning as light emitters have been synthesized. Solid-state emission reveals the exhibition of variant fluorescent color achieved by mere variation in the peripheral group attached to the core. Amongst the designed system, MBB showed a solid-state blue light emission with its emission peak centered at 453 nm. The fluorescence quantum yield of MBB displayed value of 44.82% in the solution state. Electrochemical studies on MBB estimated a HOMO energy level at −5.7 eV and LUMO at −3.2 eV. OLED realized with MBB as an active emitter material was successful in the generation of bluish-green emission with a maximum brightness of 280 cd/m2. Current efficiency of 2 cd/A and a power efficiency of 0.18 lm/W was observed for the fabricated device. © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim