Design, Synthesis and Characterization of N‐Substituted Heteroaromatics: DFT‐Studies and Organic Light Emitting Device Application. Issue 20 (26th May 2020)

• Record Type: Journal Article
• Authors: Mohan, Makesh; John, Raganjali; Nagarajan, Satyanarayan M.; Trivedi, Darshak R.
• Is Part Of: ChemistrySelect. Volume 5:Issue 20(2020)
• Page Start: 5903
• Page End: 5915
• Publication Date: 2020-05-26
• Subjects: Blue emission -- Carbazole -- Density functional calculations -- Fluorescence -- OLED; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201903409
• Languages: English
• ISSNs: 2365-6549

Abstract

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/m 2 . Current efficiency of 2 cd/A and a power efficiency of 0.18 lm/W was observed for the fabricated device. Abstract : Schiff's base condensation of 4, 5‐Dimethyl‐1, 2‐phenylenediamine and N‐(4‐Formylphenyl) carbazole (MBB ) turns out to be a good blue light‐emitting material. MBB showed the highest fluorescent quantum yield of 44.82% in the solution state with its estimated energy bandgap of 2.75 eV. Electrochemical characterization revealed MBB to possess a HOMO at −5.7 eV and LUMO at −3.2 eV. OLEDs fabricated with MBB as an active light emitter material exhibited a bluish‐green light emission.