Light-emitting diodes (LEDs) based on perovskites show great potential in lighting and display applications. However, although perovskite films with high photoluminescence quantum efficiencies are commonly achieved, the efficiencies of perovskite LEDs are largely limited by the low light out-coupling efficiency. Here, we show that high-efficiency perovskite LEDs with a high external quantum efficiency of 20.2% and an ultrahigh radiant exitance up to 114.9 mW cm⁻² can be achieved by employing the microcavity effect to enhance light extraction. The enhanced microcavity effect and light out-coupling efficiency are confirmed by the study of angle-dependent emission profiles. Our results show that both the optical and electrical properties of the device need to be optimized to achieve high-performance perovskite LEDs.

基于钙钛矿的发光二极管（LED）在照明和显示应用中显示出巨大的潜力。然而，尽管通常获得具有高光致发光量子效率的钙钛矿膜，但是钙钛矿LED的效率在很大程度上受到低的光输出耦合效率的限制。在这里，我们显示出具有20.2％的高外部量子效率和高达114.9 mW cm ^-2的超高辐射出射率的高效钙钛矿LED通过利用微腔效应来增强光提取可以实现。微腔效应和光输出耦合效率的提高已通过角度依赖性发射曲线的研究得到证实。我们的结果表明，器件的光学和电气特性都需要进行优化，以实现高性能的钙钛矿LED。