研究了不同温度下几种结构的有机电致发光器件(OLED)的瞬态电致发光响应特性以及电流密度-电压-亮度特性。研究发现, 启亮电压随温度升高而减小的加速度在200 K时出现拐点, 且这一数值主要由电子传输层Alq3的迁移率决定。当温度为200 K时, 延迟时间td最重要的影响因素是MoO3空穴注入势垒, 随着温度的升高, Δtd逐渐减小, 到300 K时基本消失。Vf代表光衰减时间随温度增长的平均速率。MoO3注入层和电致发光材料Ir(ppy)3都会对载流子的堆积起促进作用。由MoO3注入层不同引起的ΔVf是0.52 μs/K, 由电致发光材料Ir(ppy)3不同引起的ΔVf 是0.73 μs/K。

The transient electroluminescence response characteristics at different temperatures and the current density-voltage-luminance (J-V-L) characteristics of several organic light-emitting devices (OLEDs) were studied. It is found that the acceleration of the turn-on voltage decreasing with the increase of temperature appears the inflection point at 200 K, and this value mainly depends on the mobility of the electron transport layer Alq3. When the temperature is 200 K, the most important factors of delay time td is hole injection barrier MoO3. The td decreases with the increase of temperature and gradually disappears at 300 K. Vf represents the average rate of the fall time increasing with the temperature. Both MoO3 and Ir(ppy)3 can promote the accumulation of carriers. ΔVf caused by MoO3 injection layer is 0.52 μs/K, and that caused by the electroluminescent material Ir(ppy)3 is 0.73 μs/K.