کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1668000 | 1008861 | 2011 | 5 صفحه PDF | دانلود رایگان |
Using a narrow band gap host of bis[2-(2-hydroxyphenyl)-pyridine]beryllium (Bepp2) and green phosphorescent Ir(ppy)3 [fac-tris(2-phenylpyridine) iridium III] guest concentration as low as 2%, high efficiency phosphorescent organic light-emitting diode (PHOLED) is realized. Current and power efficiencies of 62.5 cd/A (max.), 51.0 lm/W (max.), and external quantum efficiency (max.) of 19.8% are reported in this green PHOLED. A low current efficiency roll-off value of 10% over the brightness of 10,000 cd/m2 is noticed in this Bepp2 single host device. Such a high efficiency is obtained by the optimization of the doping concentration with the knowledge of the hole trapping and the emission zone situations in this host–guest system. It is suggested that the reported device performance is suitable for applications in high brightness displays and lighting.
Journal: Thin Solid Films - Volume 519, Issue 10, 1 March 2011, Pages 3259–3263