Incorporation of nanomaterials in device structure is the key to enhance performance of polymer light emitting diodes (PLEDs). The major challenges that impede competence of PLEDs, for application in display technology, are (i) non-availability of stable low work function metals to act as cathode, (ii) presence of charge trapping centers in the polymer chains and (iii) total internal reflection of light at ITO/glass and glass/air interfaces. The foremost problem leads to increase in turn ON voltage of the device and reduction in electron injection from cathode. Low injection and high trapping probability of electrons lead to charge imbalance in the emissive layer and shifting of recombination zone towards cathode. This immensely constrains the formation and radiative decay of excitons in the emissive layer and declines the luminosity of the device. In this review, experimental studies on the integration of nanomaterials in PLED structures to enhance device luminance are presented. The diverse impact of their geometric features, ionization potential, electrical conductivity and refractive index on the carrier transport and light extraction in PLEDs is discussed and a perspective on this evolving research path is provided.

在器件结构中加入纳米材料是提高聚合物发光二极管 (PLED) 性能的关键。阻碍 PLED 在显示技术中应用的主要挑战是 (i) 无法获得稳定的低功函数金属作为阴极，(ii) 聚合物链中存在电荷俘获中心和 (iii) ITO/玻璃和玻璃/空气界面处的光的内反射。首要问题导致器件的导通电压增加和阴极电子注入减少。电子的低注入和高捕获概率导致发射层中的电荷不平衡和复合区向阴极移动。这极大地限制了发射层中激子的形成和辐射衰减，并降低了器件的亮度。在这篇综述中，介绍了在 PLED 结构中集成纳米材料以提高器件亮度的实验研究。讨论了它们的几何特征、电离电位、电导率和折射率对 PLED 中载流子传输和光提取的不同影响，并提供了对这一不断发展的研究路径的看法。