Heteroleptic Ir(III)-based near-infrared organic light-emitting diodes with high radiance capacity

Abstract

Near-infrared organic light-emitting diodes (NIR OLEDs) with heavy metals are regularly reported due to the advantages of their various applications in healthcare services, veil authentication, and night vision displays. For commercial applications, it is necessary to look at radiance capacity (RC) instead of radiance because of power consumption. However, recent papers still reported only simple high radiance performance and do not look at device from the point of view of RC. To overcome this hurdle, we designed Ir(III)-based heteroleptic NIR materials with two types of auxiliary ligand. The proposed emitters achieve a highly oriented horizontal dipole ratio (Ir(mCPDTiq)2tmd, complex 1: 80%, Ir(mCPDTiq)2acac, complex 2: 81%) with a short radiative lifetime (1: 386 ns, 2: 323 ns). The device also shows an extremely low turn-on voltage (Von) of 2.2 V and a high RC of 720 mW/sr/m2/V. The results on the Von and RC of the device is demonstrated an outstanding performance among the Ir(III)-based NIR OLEDs with a similar emission peak.

Azaacene containing iridium(iii) phosphors: elaboration of the π-conjugation effect and application in highly efficient solution-processed near-infrared OLEDs

“…It is noted that complex PPzIr exhibits more intense and dramatically red-shifted absorption in this region than that of DBPzIr owing to the significant extension of the conjugative structure of the PPz unit. 53 Compared to the archetype complex (qupt) 2 Ir(acac), the tert -butyl phenyl group modified heteroleptic iridium( iii ) complexes DBPzIr and PPzIr in this study show significantly red-shifted absorption arising from the conjugation effect and strengthened intramolecular charge transfer (ICT) transitions. 37 According to the absorption onsets in the neat films (Fig.…”

Ultralow Dark Current Density of Organic Photodetectors and Organic Light-Emitting Diodes Endowed by Highly Thermally Stable Derivatives of 2,7-Di-tert-butyl-9,9-dimethyl-9,10-dihydroacridine and Phenanthroimidazole Exhibiting Balanced Bipolar Charge Transport

“…As a result, hole or electron mobilities ( μ h,e ) could be calculated at different electric fields. The formula μ h,e CELIV = 2 ·d 2 /( A·t max 2 ) describing the case of the low conductivity and surface photogeneration was used . The μ h,e values estimated for the films of 5 and 6 are collected in Figure d.…”

Organic light-emitting diode (OLED) based bio-platform for phototherapeutics

“…The wound healing effects of the OLED platform were confirmed through comprehensive investigations, which demonstrated the proliferation (over 58%) and migration (over 46%) of fibroblasts under optimal conditions. Furthermore, by implementing an infrared (NIR) wavelength capable of penetrating human skin using an Ir-based NIR emitter and developing NIR OLEDs, the proliferative effects at the cellular level were successfully verified [3,4,5].…”