Phosphorescent organic light‐emitting diodes (PhOLEDs) with ultrathin emissive layer (UEML) structure have great potential in solid‐state lighting and display applications due to their relatively simple fabrication process. In this paper, the effect of doped UEML architecture on the performance of orange PhOLEDs is systematically investigated and highly efficient and long‐lifetime devices with the doped UEML structures are successfully constructed. Through strategic exciton management, the probability of exciton recombination is significantly enhanced, while simultaneously that of exciton annihilation is greatly suppressed, along with excellent charge balance. The resulting orange PhOLEDs based on tris[2‐(2‐pyridyl) imidazole] gallium(III):bis (2‐phenylbenzothiazolato) (acetylacetonate) iridium as emitter exhibit a maximum current efficiency of 60.8 cd A⁻¹, power efficiency of 65.8 lm W⁻¹, and external quantum efficiency of 23.4%, respectively. In addition, the doped UEML architecture greatly extends the device operational stability with a nearly fourfold lifetime improvement (time to reduce to 50% of the initial luminance at 2300 cd m⁻²) over the conventional phosphorescent device with doped bulk emitting layer. This should be the best results reported so far for orange PhOLEDs, indicating the use of doped UEML structure displays great potential value in designing highly efficient and long‐lifetime PhOLEDs.

中文翻译：

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超薄掺杂发光层结构的系统研究：实现高效和长寿命的橙色有机发光二极管

具有超薄发光层（UEML）结构的磷光有机发光二极管（PhOLED）由于其相对简单的制造工艺，因此在固态照明和显示应用中具有巨大的潜力。在本文中，系统地研究了掺杂UEML体系结构对橙色PhOLED性能的影响，并成功构建了具有掺杂UEML结构的高效，长寿命器件。通过战略性激子管理，激子重组的可能性大大提高，同时激子an灭的可能性大大降低，并且电荷平衡极佳。所得的基于三[2-（2-吡啶基）咪唑]镓（III）：双（2-苯基苯并噻唑并）（乙酰丙酮）铱的橙色PhOLED的最大电流效率为60。^-1的功率效率分别为65.8 lm W ^-1和23.4％的外部量子效率。另外，与具有掺杂的体发射层的常规磷光器件相比，掺杂的UEML体系结构极大地扩展了器件的操作稳定性，并且使用寿命提高了近四倍（在2300 cd m ^-2时降低到初始亮度的50％的时间）。这应该是迄今为止报道的橙色PhOLED的最佳结果，表明掺杂的UEML结构的使用在设计高效且使用寿命长的PhOLED方面显示出巨大的潜在价值。