New cyclometalated iridium(III) complex as a phosphorescent dopant in organic light emitting devices

18th International Summer School on Vacuum, Electron and Ion Technologies

Ivanov, P.^1 ; Tomova, R.^1 ; Petrova, P.^1 ; Stanimirov, S.^2 ; Petkov, I.^2

Acad. J. Malinowski Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 109, 1113 Sofia, Bulgaria^1

Laboratory of Organic Photochemistry, Faculty of Chemistry and Pharmacy, St. Kl. Ohridski University of Sofia, 1 James Baurchier Blvd., 1164 Sofia, Bulgaria^2

关键词: Cyclometalated iridium(III) complexes;    Electroluminescence spectra;    Electroluminescent intensity;    Electron transporting layer;    Hole transporting layers;    Organic light-emitting devices;    Phosphorescent dopant;    Poly(N-vinylcarbazole);   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/514/1/012038/pdf
DOI  :  10.1088/1742-6596/514/1/012038

来源: IOP

【 摘 要 】

A new cyclometalated iridium (III) bis[2-(4-chlorophenyl)benzothiazolato-N, C2]-acetylacetonate, (Cl-bt)2Ir(acac), was synthesized and identified by1H NMR and elemental analysis. The application was studied of the new compound as a dopant in the hole transporting layer (HTL) of the following organic light emitting diode (OLED) structure: HTL/EL/ETL, where HTL was 4,4'-bis(9H-carbazol-9-yl)biphenyl (CBP) or N,N'-bis(3-methylphenyl)-N, N'-diphenylbenzidine (TPD), incorporated in a poly(N-vinylcarbazole) (PVK) matrix; EL was an electroluminescent layer of bis(8-hydroxy-2-methylquinoline)- (4-phenylpheno-xy) aluminum (BAlq); and ETL was an electron-transporting layer of bis[2-(2-benzothiazoly) phenolato]zinc(II) (Zn(btz)2). We established that the electroluminescence spectra of the OLEDs at different dopant concentrations were basically the sum of the greenish-blue emission of BAlq and the yellowish-green emission of the Ir complex. It was also found that increasing the dopant concentration resulted in an increase in the relative electroluminescent intensity of the Ir complex emission, while that of BAlq decreased, thus a fine tuning of the OLED color was observed.