红光量子点掺杂PVK体系的发光特性研究

摘要

Multilayer electroluminescent devices with a system in which red-emitting quantum dots doped PVK serves as the active layer is fabricated through non-treatment process, the device structure being ITO/PVK:QDs/Alq3/Al. Measuring the emission spectra and electrical characteristics of the devices we study the effect of different QDs doping concentration (mass fraction), and propose some possible solutions to optimize the PVK:QDs system after taking pure QDs for comparison. Experimental results show that changing QDs doping concentration would bring significant impact on the electroluminescence (EL) spectra, current density, brightness, and the stability of devices. When QDs doping concentration is low, we will mainly see the light of Alq3; when QDs doping concentration is 20%, saturated pure red light emission is observed and it is brighter than other devices. However, when the doping concentration is high, a slight red shift occurs in the EL spectra, and the performance of the device gets worse. With a suitable doping concentration, the PVK:QDs may increase the stability of devices.%无热处理制备了红光CdSe/ZnS量子点掺杂PVK的ITO/PVK：QDs/Alq3/Al结构电致发光器件。测试器件的发光光谱和电学特性等，研究了掺杂浓度(质量分数)对体系发光特性的影响，将非掺杂与掺杂体系做了比较，提出了优化掺杂体系的一些可行方案。量子点掺杂浓度较低时，主要为Alq3的发光；掺杂浓度为20%时， Alq3的发光得到抑制，红光发射最佳；继续增大掺杂浓度， QDs发光峰发生微弱红移，器件性能变差。与非掺杂体系相比，掺杂浓度合适的PVK：QDs体系大大提高了器件的稳定性。