Theoretical assessments and optical and electrochemical properties of the alkoxylated bischalcone as emissive material in single-layer OLED.

Abstract

A new bischalcone comprising of hexyloxy (-OC6H2n+1) chain based on 'Donor (D)-π-Donor (D)' system was successfully designed and synthesized to demonstrate as emitting material for single-layer OLEDs. Density functional theory (DFT) assessment at B3LYP/6-31G(d,p) was computed to obtain frontier molecular orbitals (FMOs), chemical reactivity and molecular electrostatic potential (MEP). The utilization of alkoxy substructure towards the chalcone moiety has increased the solubility and contributed to HOMO-LUMO gap energy level 3.473eV by UV-Vis spectroscopy and was found to have good agreement with the theoretical calculations. The investigations on their optical, electrochemical and thermal behaviour also were conducted via UV-Vis, cyclic voltammetry (CV), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The entitled alkoxylated bischalcone (CSAB) revealed good thermal stability up to 300°C and showed high glass transition temperatures. At positive potential, a quasi-reversible oxidation (Eox 1/2) peak at 2.40V and negative potentials exhibited reduction peak at 0.78V, respectively. The application of CSAB was tested in the form of thin film in respect to its conductivity in terms of electrical current and electroluminescence behaviour. It gave an intense yellow emission which has provided depth fundamental understanding on its potentiality featuring alkoxylated bischalcone moiety as solution-processed OLED material in optoelectronic interests.