Device stability of the organic light emitting diodes is strongly affected by accumulated charge carriers at both interfaces of emitting layer (EML). To reduce the stress of devices from undesirable charge accumulation near EML, an interface tunneling layer (ITL) is introduced. Notably, ITL affects charge injection behavior, which helps to reduce a chemical degradation of EML. As a result, significantly improved device lifetime (by 2.5 times, ≈402.1 h, LT 75) after the introduction of pretty thin (1 nm) ITL between EML and electron transporting layer is obtained. Such a tunneling behavior by analysis of impedance spectroscopy (IS), ultraviolet photoelectron spectroscopy (UPS), and electric stress for electron and hole only devices are verified.

中文翻译：

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通过超薄界面隧穿层实现稳定的绿色PHOLED的有机界面工程

有机发光二极管的器件稳定性受发光层（EML）的两个界面处累积的电荷载流子的强烈影响。为了减少由于EML附近不希望的电荷积累而引起的设备压力，引入了接口隧穿层（ITL）。值得注意的是，ITL影响电荷注入行​​为，这有助于减少EML的化学降解。结果，在EML和电子传输层之间引入了非常薄（1 nm）的ITL之后，获得了显着改善的器件寿命（提高了2.5倍，≈402.1h，LT 75）。通过分析阻抗谱（IS），紫外线光电子谱（UPS）和仅电子和空穴器件的电应力，验证了这种隧穿行为。