Highly Efficient Orange and White Organic Light‐Emitting Diodes Based on New Orange Iridium Complexes

Abstract

Highly efficient, orange organic light‐emitting diodes (OLEDs) fabricated from newly synthesized iridium complexes show a maximum luminance efficiency of 76 cd A−1 and a peak power efficiency of 45 lm W−1. The white OLEDs containing the orange iridium and traditional blue iridium phosphors exhibit extraordinarily high efficiencies and a peak external quantum efficiency of 26%.

Novel Ir(ppy)3 Derivatives: Simple Structure Modification Toward Nearly 30% External Quantum Efficiency in Phosphorescent Organic Light‐Emitting Diodes

“…We propose that the remarkably high phosphorescence quantum yield of 6F may be because of the extra donation of six F atoms which are famous for their special function to increase luminescence quantum yield. [ 14 ] In spite of the high phosphorescent quantum yield, 6F still exhibited rather low external quantum yield like 3F in its PhOLED, this coincides with its weaker coordination. Besides, the other possible mechanism for the different performance of these multifl uorinated iridium complexes is still under research in our lab.…”

“…Both ligands L-1F-DPA and L-2F-DPA have the same 2-phenylpyridine (ppy) framework. Since it was verifi ed that fl uorination was an effective strategy to improve luminescent quantum yield for some iridium complexes, [ 14 ] and diphenylamino (DPA) is an well-known hole-transporting group, the DPA was introduced into the pyridine ring and one or two fl uorine atoms incorporated into the phenyl moiety of ppy to design the cyclometalating ligands L-1F-DPA and L-2F-DPA, with expectation to tune the electronic states and photophysical and electrochemical properties of the fi nal iridium complexes. By varying the applied molar ratio of ligands L-1F-DPA and L-2F-DPA in the synthetic procedure, four tris-cyclometalated iridium complexes were generated with the fl uorine (F) atom number on the ligands regularly varying from 3 to 6, accordingly named as 3F , 4F , 5F, and 6F for easy identifi cation.…”

Organometallic Versus Organic Molecules for Energy Conversion in Organic Light-Emitting Diodes and Solar Cells

“…Furthermore, when Ir-1 was used to fabricate two-element WOLEDs in combination with FIrpic, high efficiencies of 57.9 cd/A and 21.9 % were achieved. A two-element WOLED with a peak η L of 68 cd/ A was also demonstrated using a related derivative as an orange emitter [22]. Another two-color WOLEDs with good performance based on blue-emitting FIrpic and PQ2Ir as a complementary red emitter was reported by Su and coworkers, in which the η ext of 25 % and η P of 46 lm/W were achieved at 1,000 cd/m 2 [30].…”

“…For example, incorporating different substituents at different positions of the 2-phenylpyridine ligand framework has resulted in a continuous tuning of the phosphorescence of their homoleptic iridium(III) complexes from sky blue (468 nm) to orange-red (595 nm) [20,21]. White OLED (WOLED) technology has attracted much attention because of its great potential in solid-state lighting and displays [22]. The first WOLEDs comprising small organic molecules were reported by Kido [23][24][25].…”

Recent progress in the use of fluorescent and phosphorescent organic compounds for organic light-emitting diode lighting

“…74 The synthesized material showed high efficiency with an LE of 20.2 cd∕A and PE of 23.6 lm∕W for a CIE of (0.53, 0.46). 75 This emitter 83 showed extremely high efficiency for a CIE of (0.52, 0.47), with an LE of 76 cd∕A and PE of 45 lm∕W (see Fig. 13).…”