Triphenylsilyl-Promoted Iridium Complex for High-Performance Green-Yellow Phosphorescent Organic Light-Emitting Diodes

Abstract

In this work, a novel triphenylsilyl-based iridium complex, fac-Ir­(tpsp)2(bpp), is developed. Triphenylsilyl groups endow fac-Ir­(tpsp)2(bpp) with favorable intermolecular interactions. On the one hand, the steric hindrance of a triphenylsilyl group significantly weakens intermolecular π···π interactions. On the other hand, triphenylsilyl ligands provide several C–H···π interactions for fac-Ir­(tpsp)2(bpp). As a result, fac-Ir­(tpsp)2(bpp) exhibits a high sublimation yield (78.2%), high photoluminescence quantum yield (97.6%), short lifetime (510.9 ns), low concentration sensitivity (10–6 to 10–4 M), and moderate charge-transporting ability. Phosphorescent devices that utilize fac-Ir­(tpsp)2(bpp) as the emitter display high efficiencies (100.9 cd/A, 105.6 lm/W, 27.9%), low roll-off of efficiencies (from 100 to 10,000 cd/m2: 5.3%), relatively low concentration sensitivity (from 5 to 12%), long device lifetime (61,892 h at 100 cd/m2), and very stable electroluminescent spectra (from 1 to 70,000 cd/m2). This performance is comparable to those of previous record green/yellow phosphorescent emitters. More importantly, most of record emitters report limited excellent parameters, and comprehensive emitter-like fac-Ir­(tpsp)2(bpp) is rare. These results demonstrate that fac-Ir­(tpsp)2(bpp) is a good phosphorescent emitter.

Wet Film Leveling for Promoting the Uniformity and Conductivity of Silver Nanowire Transparent Electrode

“…The used materials were reported in our previous work. 35,36 The device performance was exhibited in Figure 9 and Figure S16. The turn-on voltage, maximum brightness, maximum current, power, and external quantum efficiencies of ITO-based OLED were 2.6 V, 91019 cd m −2 , 71.3 cd/A, 79.9 lm/W, and 16.90%, respectively.…”

The design and synthesis of green emissive iridium(iii) complexes guided by calculations of the vibrationally-resolved emission spectra

“…Examples of groups that can suppress vibronic coupling in iridium complexes can be as small as a methyl group, 15 or longer alkyl chains, 16 aryl groups 11,17 or heteroatom-containing functional groups such as silanes. [18][19][20][21][22][23][24] Previously reported iridium complexes containing trimethylsilyl groups on a ppy ligand are shown in Chart 1 and their photophysical properties are reported in Table 1. One available yet underutilised tool to study vibrational coupling in emissive complexes is to calculate the vibrationally coupled emission spectrum.…”

The design and synthesis of green emissive iridium(III) complexes guided by calculations of the vibrationally-resolved emission spectra

“…Examples of groups that can suppress vibronic coupling in iridium complexes can be as small as a methyl group, 15 or longer alkyl chains, 16 aryl groups 11,17 or heteroatom-containing functional groups such as silanes. [18][19][20][21][22][23][24] Previously reported iridium complexes containing trimethylsilyl groups on a ppy ligand are shown in Figure 2 and their photophysical properties are reported in Table 1. One available yet underutilised tool to study vibrational coupling in emissive complexes is to calculate the vibrationally coupled emission spectrum.…”