Lead halide perovskite (LHP) nanocrystals (NCs) suffer from poor stability against environmental factors (heat, moisture, oxygen, etc.), which seriously hinders their practical application. Constructing a core-shell structure could be an effective approach to improve the stability and optical properties of the LHP NCs. Herein, a novel strategy of water-triggered phase transformation and phospholipid (DSPE) micelle encapsulation is proposed, generating highly luminescent water-dispersed CsPbBr₃@CsPb₂Br₅@DSPE core-shell-shell nanocrystals. The epitaxial growth of the CsPb₂Br₅ shell is induced by the in-situ reconstruction of the CsPbBr₃ surface by water erosion, and the lattice mismatch with the CsPbBr₃ core is small (3.8%). The further amphipathic phospholipid encapsulation guarantees their excellent water dispersity and stability. Revealed by the femtosecond transient absorption spectroscopy, the dense CsPb₂Br₅@DSPE shell effectively passivates the surface of the CsPbBr₃ core, thus improving its stability and luminescence performance. The resulting CsPbBr₃@CsPb₂Br₅@DSPE nanoparticles exhibit excellent performance as fluorescent probes for bioimaging, aqueous inks for high-resolution pattering, and light conversion layers for LEDs, demonstrating their promising potential in multiple applications.

中文翻译：

---

用于生物成像、图案和 LED 的高发光水稳定CsPbBr3@CsPb2Br5@DSPE核壳钙钛矿纳米晶体的结构重构合成


卤化铅钙钛矿 （LHP） 纳米晶 （NCs） 对环境因素（热、湿、氧等）的稳定性较差，严重阻碍了其实际应用。构建核壳结构可能是提高 LHP NCs 稳定性和光学性能的有效途径。在此，提出了一种水触发相变和磷脂 （DSPE） 胶束封装的新策略，生成高发光水分散的 CsPbBr₃@CsPb₂Br₅@DSPE 核壳纳米晶。CsPb₂Br₅ 壳层的外延生长是由水侵蚀对 CsPbBr₃ 表面的原位重建诱导的，与 CsPbBr₃ 核心的晶格失配很小 （3.8%）。进一步的两亲性磷脂包封保证了它们出色的水分散性和稳定性。飞秒瞬态吸收光谱显示，致密的 CsPb₂Br₅@DSPE 壳层有效地钝化了 CsPbBr₃ 核心的表面，从而提高了其稳定性和发光性能。所得的 CsPbBr₃@CsPb₂Br₅@DSPE 纳米颗粒作为生物成像的荧光探针、用于高分辨率图案的水性油墨和 LED 的光转换层表现出优异的性能，展示了它们在多种应用中的潜力。