Details

Autor(en) / Beteiligte

• Peng, Tai
• Li, Guomeng
• Ye, Kaiqi
• Huang, Shuo
• Wu, Ying
• Liu, Yu
• Wang, Yue

Titel

Concentration-insensitive and low-driving-voltage OLEDs with high efficiency and little efficiency roll-off using a bipolar phosphorescent emitter

Ist Teil von

• Organic electronics, 2013-06, Vol.14 (6), p.1649-1655

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• [Display omitted] •Highly efficient PHOLEDs based on a bipolar iridium emitter have been demonstrated.•PHOLEDs show gratifying concentration-insensitive and low-driving-voltage feature.•EQE values maintain at more than 20% in very wide luminance range of 1–15,000cdm−2. A series of simplified trilayer phosphorescent organic light-emitting diodes (PHOLEDs) with high efficiency and little efficiency roll-off based on a bipolar iridium emitter Iridium(III) bis(2-phenylpyridinato)-N,N′-diisopropyl-diisopropyl-guanidinate (ppy)2Ir(dipig) has been demonstrated. They are dominated by the efficient direct-exciton-formation mechanism and show gratifying concentration-insensitive and low-driving-voltage features. In particular, very high and stable electroluminescence (EL) efficiencies (maximum power efficiency and external quantum efficiency >98lmW−1 and 25% respectively, and external quantum efficiency >20% over a wide luminance range of 1–15,000cdm−2) are achieved in the PHOLEDs based on emitting layers (EMLs) consisting of (ppy)2Ir(dipig) codeposited with common host CBP in an easily controlled doping concentration range (15–30wt%). The EL performance of the PHOLEDs is comparable to the highest PHOLEDs reported in scientific literature.