Fabrication of non-doped red organic light emitting diode using naturally occurring Curcumin as a donor-acceptor-donor (D-A-D) emitting layer with very low turn-on voltage

The fabrication of a non-doped red organic light-emitting device (OLED) has been developed using naturally occurring curcumin as an emissive layer of OLED. In this research, the electroluminescent spectrum (EL) of curcumin as a donor-acceptor-donor (D-A-D) chromophore was obtained at wavelength of 612 nm. Also, the maximum external quantum efficiencies (EQE) for this device was measured and found to be 0.029 %. The device was characterized by low driving voltage below 1 V at a current density of 7 mA/cm2. High color purity with Commission International de l’Eclairage coordinates was measured and found to be (0.544, 0.441). Quantum mechanical calculations were achieved base on DFT/B3LYP/6-311G (d,p) level of theory to rationalize the optical properties, indicating the optimized energy and computing the HOMO-LUMO values. Good conformity was observed between theoretical and experimental data.