Metal halide perovskite nanocrystals (NCs) have sparked considerable attentions in the area of light-emitting diodes (LED) by virtue of their remarkable color purity and spectral tunability (400–700 nm). However, the optoelectronic performance of LED devices based on perovskite NCs is severely limited by the problem of charge injection since (i) the charge injection layers exhibit significant differences in energy levels and charge mobility, (ii) one thick NCs emitting layer can obstruct the electrons transmission and one thin NCs emitting layer can change the charge recombination region, inducing series of troubles in fabrication and application of LED devices. Herein, a series of LED devices based on cesium lead bromide (CsPbBr₃) green-emitting perovskite NCs are reported by adopting Poly-N-vinylcarbazole (PVK)/Poly [9,9-dioctylfluoreneco-N-[4-(3-methylpropyl)]diphenylamine] (TFB) and Poly[bis(4-phenyl) (2,4,6-trimethylphenyl)amine] (PTAA) as the hole transport layer (HTL) materials. With the increase of applied voltage, the CsPbBr₃ NCs LED device with PTAA as HTL displays better transport characteristics, such as a lower turn-on voltage and a higher luminance, than that of the device with TFB and PVK as HTL. By optimizing the spin-coating craft parameter of the CsPbBr₃ NCs layer, an efficient green-emitting CsPbBr₃ NCs LED device with maximum luminance of 4531 cd m⁻², current efficiency of 14.4 cd A⁻¹, power efficiency of 14.1 lm W⁻¹ and maximum external quantum efficiency of 4.28% was obtained. These results provide an approach for the practical applications of CsPbBr₃ NCs electroluminescence LED devices.

金属卤化物钙钛矿纳米晶体（NCs）凭借其卓越的色纯度和光谱可调性（400–700 nm），在发光二极管（LED）领域引起了相当大的关注。但是，基于钙钛矿型NC的LED器件的光电性能受到电荷注入问题的严重限制，因为（i）电荷注入层的能级和电荷迁移率存在显着差异，（ii）一个厚的NCs发射层会阻碍电荷注入。电子传输和一个薄的NCs发射层会改变电荷复合区域，从而在LED器件的制造和应用中引起一系列麻烦。本文介绍了一系列基于溴化铯（CsPbBr ₃）通过采用聚-N-乙烯基咔唑（PVK）/聚[9,9-二辛基芴-N- [4-（3-甲基丙基）]二苯胺]（TFB）和聚[双（4-苯基）（2,4,6-三甲基苯基）胺]（PTAA）作为空穴传输层（HTL）的材料。随着施加电压的增加，与以TFB和PVK为HTL的器件相比，以PTAA作为HTL的CsPbBr ₃ NCs LED器件具有更好的传输特性，例如更低的导通电压和更高的亮度。通过优化CsPbBr ₃ NCs层的旋涂工艺参数，可以得到一种高效的绿色发射CsPbBr ₃ NCs LED器件，其最大亮度为4531 cd m ^-2，电流效率为14.4 cd A ^-1，获得了14.1 lm W ^-1的功率效率和4.28％的最大外部量子效率。这些结果为CsPbBr ₃ NCs电致发光LED器件的实际应用提供了一种方法。