The performance of perovskite light-emitting diodes (PeLEDs) has progressed rapidly in recent years, with electroluminescence efficiency now reaching 20%^{1,2,3,4,5,6,7,8,9,10,11,12}. However, devices, so far, have featured small areas and usually show notable variation in device-to-device performance. Here, we show that the origin of suboptimal device performance stems from inadequate hole injection, and that the use of a hole-transporting polymer with a shallower ionization potential can improve device charge balance, efficiency and reproducibility. Using an ITO/ZnO/PEIE/FAPbI₃/poly-TPD/MoO₃/Al device structure, we report a 799 nm near-infrared PeLED that operates with an external quantum efficiency (EQE) of 20.2%, at a current density of 57 mA cm⁻² and a radiance of 57 W sr⁻¹ m⁻². The standard deviation in the device EQE is only 1.2%, demonstrating high reproducibility. Large-area devices measuring 900 mm² operate with a high EQE of 12.1%, and are shown to suit medical applications such as subcutaneous deep-tissue illumination and heart rate monitoring.

钙钛矿发光二极管（PeLED）的性能近年来发展迅速，电致发光效率现已达到20％^{1,2,3,4,5,6,7,8,9,10,11,12}。但是，到目前为止，设备的区域很小，通常在设备之间的性能上表现出明显的差异。在这里，我们表明次优器件性能的起因是空穴注入不足，并且使用电离势较浅的空穴传输聚合物可以改善器件电荷平衡，效率和可重复性。我们使用ITO / ZnO / PEIE / FAPbI ₃ / poly-TPD / MoO ₃ / Al器件结构，报告了一种799 nm近红外PeLED，其电流密度为20.2％，外部量子效率（EQE）为20.2％。 57 mA厘米^-2和57 W sr ^-1  m ^-2的辐射。器件EQE的标准偏差仅为1.2％，表明具有很高的重现性。面积为900 mm ^2的大面积设备可以以12.1％的高EQE正常运行，并且被证明适合于医疗应用，例如皮下深层组织照明和心率监测。