The thermal quenching of light emission is a critical bottleneck that hampers the real-world application of lead halide perovskite nanocrystals in both electroluminescent and down-conversion light-emitting diodes. Here, we report CsPbBr₃ perovskite nanocrystals with a temperature-independent emission efficiency of near unity and constant decay kinetics up to a temperature of 373 K. This unprecedented regime is obtained by a fluoride post-synthesis treatment that produces fluorine-rich surfaces with a wider energy gap than the inner nanocrystal core, yielding suppressed carrier trapping, improved thermal stability and efficient charge injection. Light-emitting diodes incorporating these fluoride-treated perovskite nanocrystals show a low turn-on voltage and spectrally pure green electroluminescence with an external quantum efficiency as high as 19.3% at 350 cd m⁻². Importantly, nearly 80% of the room-temperature external quantum efficiency is preserved at 343 K, in contrast to the dramatic drop commonly observed for standard CsPbBr₃ perovskite nanocrystal light-emitting diodes. These results provide a promising pathway for high-performance, practical light-emitting diodes based on perovskite nanostructures.

发光的热猝灭是阻碍卤化铅钙钛矿纳米晶体在电致发光和下转换发光二极管中的实际应用的关键瓶颈。在这里，我们报告 CsPbBr ₃钙钛矿纳米晶体具有与温度无关的接近统一的发射效率和恒定衰减动力学，最高温度可达 373 K。这种前所未有的状态是通过氟化物后合成处理获得的，该处理产生具有比内部更宽的能隙的富氟表面纳米晶核，产生抑制的载流子俘获，改善的热稳定性和有效的电荷注入。^{包含这些经氟化物处理的钙钛矿纳米晶体的发光二极管显示出低开启电压和光谱纯绿色电致发光，在 350 cd m -2}下具有高达 19.3% 的外部量子效率。重要的是，近 80% 的室温外部量子效率保持在 343 K，与标准 CsPbBr 通常观察到的急剧下降形成对比_3个钙钛矿纳米晶发光二极管。这些结果为基于钙钛矿纳米结构的高性能、实用的发光二极管提供了一条有希望的途径。