Cesium lead halide perovskite crystals have attracted widespread attention due to their excellent photoelectric properties. However, their intrinsic instability and the photoluminescence quantum yield (PLQY) sharply dropped in the solid-state limit their practical applications. Besides, the current synthesis strategies either need a variety of ligands, or an anti-solvent, which will result in potential environmental risks. Herein, we address the above issues simultaneously by embedding CsPbBr₃ in a large bandgap Cs₄PbBr₆ matrix by high-speed mechanical mixing without using any ligands and highly toxic anti-solvent. Changing the molar ratio of PbBr₂/CsBr, centrifugation time, and the solution concentration, the optimized CsPbBr₃/Cs₄PbBr₆ show a high PLQY of up to 79%. In addition, mechanistic studies show that the origin of green luminesce of CsPbBr₃/Cs₄PbBr₆ microcrystals is closely related to the CsPbBr₃ inclusion theory, but not to the Br vacancy theory, in which CsPbBr₃ embedded in Cs₄PbBr₆ to form a CsPbBr₃/Cs₄PbBr₆ heterostructure. By taking advantage of the heterostructure, the photostability and thermostability of CsPbBr₃/Cs₄PbBr₆ are significantly enhanced. In addition, the high optical and temperature/humidity-stable performances of CsPbBr₃/Cs₄PbBr₆ are verified by applying them to white LEDs (WLEDs). The electroluminescence intensity of WLEDs remains 70% of the original one after being stored in a chamber with high temperature and high humidity (85 °C/RH 85%) for 40 h, and the device displays luminous efficiency of 74.5 lm/W at 20 mA. This result provides a solid foundation for their scale applications in lighting, displays, and other optoelectronic and photonic devices.

铯铅卤化钙钛矿晶体由于其优异的光电性能而受到广泛关注。然而，它们固有的不稳定性和固态下的光致发光量子产率（PLQY）急剧下降，限制了它们的实际应用。此外，目前的合成策略要么需要多种配体，要么需要反溶剂，这将导致潜在的环境风险。在此，我们通过高速机械混合将CsPbBr ₃嵌入到大带隙Cs ₄ PbBr ₆基质中，同时不使用任何配体和剧毒抗溶剂，从而同时解决上述问题。改变PbBr ₂ /CsBr的摩尔比、离心时间和溶液浓度，优化的CsPbBr₃ /Cs ₄ PbBr ₆表现出高达 79% 的高 PLQY。此外，机理研究表明，CsPbBr ₃ /Cs ₄ PbBr _{6微晶的绿光起源与 CsPbBr 3}夹杂理论密切相关，但与 CsPbBr ₃嵌入 Cs ₄ PbBr ₆中的 Br 空位理论无关。形成CsPbBr ₃ /Cs ₄ PbBr ₆异质结构。通过利用异质结构，CsPbBr ₃ /Cs ₄ PbBr _{6的光稳定性和热稳定性}显着增强。此外，CsPbBr ₃ /Cs ₄ PbBr ₆的高光学和温度/湿度稳定性性能通过将它们应用于白光 LED (WLED) 得到验证。在高温高湿（85°C/RH 85%）的箱体中存放40 h后，WLED的电致发光强度仍为原来的70%，器件在20℃时的发光效率为74.5 lm/W嘛。这一结果为其在照明、显示器和其他光电和光子器件中的大规模应用提供了坚实的基础。