Quantum dots (QDs) are electroluminescent (EL) materials that have been developed as promising emitters in next-generation displays. The amount of charge carriers that travel to the light-emitting layer located at the interface between the hole- and electron-transport layers must be balanced in these displays to achieve maximum luminous efficiency. An existing amine ligand (oleylamine), which was coordinated on the surface of red-emitting InP/ZnSeS/ZnS QDs, was partially exchanged with two 2,2′-bipyridyl derivatives to enhance the EL properties; the QD light-emitting diode (QD-LED) performance was also investigated. Thermogravimetric and ¹H nuclear magnetic resonance analyses were used to examine the bipyridyl-ligand-partially-substituted QDs. Photoluminescence spectroscopy and transmission electron microscopy revealed that the emission wavelength (630 nm) and size (7.3 nm) of the QDs were not altered upon ligand exchange. Significant improvements were observed in the electronic properties of QD-LED devices fabricated using the bipyridyl-ligand-substituted QDs. The bipyridyl ligands lowered the charge-injection barrier and improved the charge balance in the QDs. High-performance QD-LED devices were consequently realized with an augmentation of two times in current density, and three times in brightness, external quantum efficiency, and current efficiency.

量子点 (QD) 是电致发光 (EL) 材料，已被开发为下一代显示器中很有前途的发射器。在这些显示器中，必须平衡传输到位于空穴传输层和电子传输层之间界面处的发光层的电荷载流子的数量，以实现最大的发光效率。现有的胺配体（油胺）配位在发红光的 InP/ZnSeS/ZnS QDs 表面，与两个 2,2'-联吡啶衍生物部分交换以增强 EL 性能；还研究了 QD 发光二极管 (QD-LED) 的性能。热重和¹H 核磁共振分析用于检查联吡啶配体部分取代的量子点。光致发光光谱和透射电子显微镜显示 QD 的发射波长 (630 nm) 和大小 (7.3 nm) 在配体交换时没有改变。使用联吡啶配体取代的 QD 制造的 QD-LED 器件的电子特性得到显着改善。联吡啶配体降低了电荷注入势垒并改善了量子点中的电荷平衡。因此实现了高性能 QD-LED 器件，电流密度增加了两倍，亮度、外部量子效率和电流效率增加了三倍。