PtOEP掺杂Alq_3有机发光器件的能量传递

Energy transfer in PtOEP doped Alq_3 organic light-emitting devices

研究了高效磷光染料八乙基卟啉铂(PtOEP)掺杂于主体材料八羟基喹啉铝(Alq3)体系中PtOEP、Alq3之间的能量传输机制。分别以PtOEP掺杂和未掺杂的Alq3膜作为发光层制作有机发光器件(OLED),改变掺杂浓度,检测器件电致发光(EL)光谱的变化。经分析,在5%、10%、20%三种掺杂浓度中,10%掺杂浓度能量传递效果最好。通过对掺杂和未掺杂器件电流密度-电压、亮度-电压数据检测,计算外量子效率,在低电流密度(≤7mA/cm2)驱动下掺杂器件外量子效率是未掺杂器件的5倍。

Employing 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine platinum（Ⅱ） （PtOEP） as a phosphorescent dye, doped into 8-hydroxyquinoline aluminum （A1q3） host, the mechanism of energy transfer is demonstrated. Organic light-emitting devices （OLEDs） are fabricated by using PtOEP doped A1q3 or only A1q3 as light emitting layer, respectively The electroluminescence spectra of devices with different doping concentration are detected under different driving current densities. Through the analysis of the spectra, the mechanism of energy transfer and the optical properties between PtOEP and A1q3, we conclude that 10% （by weight） doping concentration is optimal concentration. The external quantum efficiencies （QE） are calculated according to the current density-voltage and luminescence-voltage data. It is shown that the QE of devices with 10% PtOEP doping concentration is five times more than that of A1q3 only device under low driving current density （≤7 mA/cm^2）.