Efficiency phosphorescent OLEDs with a low roll-off based on a hetero-triplet iridium complex
Source abstract
Abstract
Abstract In order to explore the triplet–triplet annihilation in cyclometalated iridium complexes, a hetero-triplet iridium complex [Ir(ppy) 2 pbi] employing two 2-phenylpyridine (Hppy) ligands and one 1,2-diphenyl-1 H -benzo[ d ]-imidazole (Hpbi) ligand with similar triplet energies was synthesized. A device based on Ir(ppy) 2 pbi exhibited high current efficiency 26.7 cd/A at high doping concentration 12 wt%. More interestingly, the current efficiency was still maintained at 25.8 cd/A when the current density was above 253.2 mA/cm 2 . The efficiency roll-off was only about 3.4%, much lower than that of traditional cyclometalated iridium complexes. It is proposed that the complicated energy level and unsymmetical ligand in Ir(ppy) 2 pbi may help to suppress the triplet–triplet annihilation.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Organic Light-Emitting Diodes Research · Luminescence and Fluorescent Materials · Organic Electronics and Photovoltaics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (33)
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