Saturated-blue-emitting [3+2+1] coordinated iridium(iii) complexes for vacuum-deposited organic light-emitting devices

Abstract

A new class of deep-blue phosphorescent [3+2+1] coordinated iridium (III) complexes containing phenyl-3H-imidazo[4,5-b]pyridine-based (C^C) bidentate ligands has been synthesized, characterized, and applied as phosphorescent dopants in the fabrication of vacuum-deposited...

New [3+2+1] Iridium Complexes as Effective Phosphorescent Sensitizers for Efficient Narrowband Saturated–Blue Hyper–OLEDs

“…The target complexes B-4-TMS and B-5-TMS were obtained from the reaction of the corresponding bromide intermediates (PB-4-TMS and PB-5-TMS) with silver cyanide (AgCN) in dimethyl formamide (DMF) solution. The precursors and the ligands were prepared according to the literature, [17,[31][32][33][34] and all the compounds were characterized by 1 H NMR and 19 F NMR spectroscopy and mass spectrometry (see the Experimental Section Figures S1-S18, Supporting Information). The thermal stability of the iridium complexes was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) (Figures S19 and S20 and Table S2, Supporting Information).…”

Blue Iridium (III) Phosphorescent OLEDs with High Brightness Over 10 000 cd m−2 and Ultralow Efficiency Roll‐Off

“…However, complexes 4 and 6 exhibited a red-shifted emission and complex 3 showed a vibronic-structural emission spectra, indicating that the polarity of the solvent and the molecular packing styles in the solid condition may also affect the emissive state and in turn the emission spectra. [38,43,49,50] Specifically, complexes 3 and 6 exhibit almost unity internal quantum efficiency with short excited state lifetime value down to 1 µs in the 10 wt% doping in co-host (mCBP: B4PymPm = 1:1) thin-film, indicating a high k r of up to 10 6 s −1 (see Figure 2d and Table 2), highly comparable to the most advanced iridium(III), [51][52][53][54][55] platinum(II), [56][57][58] and TADF-gold(III) emitters. [59][60][61] Such observations suggested that the short-excited state properties of the complexes are also beneficial to reduce the annihilation process due to the rapid radiative decay.…”