Highly Stable CsPbBr3@Cs4PbBr6 Perovskite Fluorescent Nanomaterials for White Light-Emitting Diodes

en This link goes to a English section zh This link goes to a Chinese section Although halide perovskite nanocrystals exhibit excellent photoelectric properties, their inherent instability greatly limits their practical applications. Here, we report a novel self-assembly strategy to synthesize highly stable CsPbBr 3 @Cs 4 PbBr 6 perovskite fluorescent nanomaterials in a single step by using 4,4′-azo (4-cyanoglutaric acid, CA) and oleylamine (OAm) as ligands, with HBr introduced during the preparation process to create a Br-rich reaction environment. Specifically, the ligands CA and OAm are anchored to the surface of the composite and then effectively improve their optical properties. Interestingly, because of the protective effect of Cs 4 PbBr 6 , the as-synthesized CsPbBr 3 @Cs 4 PbBr 6 micromaterials demonstrate excellent solution stability, photostability, and thermal cycling stability. Moreover, the combined effects of the reduction in particle size of CsPbBr 3 @Cs 4 PbBr 6 and the decomposition of CsPbBr 3 into CsBr and PbBr 2 are found to induce an initial increase and subsequent decrease in its luminescence intensity in polar media. The as-synthesized perovskite luminescent materials, when combined with Gd 2 O 3 :Eu red phosphor and Ba 2 Sr(PO 4 ) 2 :1% Eu 2+ blue phosphor, form a white light-emitting diode (WLED) device that exhibits outstanding luminous properties. This work not only provides a novel approach for the stable synthesis of perovskite luminescent nanoparticles but also lays a foundation for their application in LED technologies. 摘要 en This link goes to a English section zh This link goes to a Chinese section 尽管卤化物钙钛矿材料具有出优异的光电性能,但其固有的不稳定性极大地限制了它们的实际应用。在此,本研究创新性地采用自组装策略,使用4-氰基戊二酸(CA)和油胺(OAm)作为配体,并在制备过程中引入HBr以创建富溴反应环境,通过一步法合成高稳定性的CsPbBr 3 @Cs 4 PbBr 6 钙钛矿发光材料。具体而言,配体CA和OAm锚定在复合材料表面,从而有效改善了它们的光学性能。有趣的是,由于Cs 4 PbBr 6 的保护作用,所合成的CsPbBr 3 @Cs 4 PbBr 6 微材料表现出优异的溶液稳定性、光稳定性和热循环稳定性。此外,研究发现,CsPbBr 3 @Cs 4 PbBr 6 粒径的减小和CsPbBr 3 分解为CsBr和PbBr 2 的共同作用,导致其在极性介质中的发光强度先增加后减少。所合成的钙钛矿发光材料与Gd 2 O 3 :Eu红色荧光粉和Ba 2 Sr(PO 4 )2:1% Eu 2+ 蓝色荧光粉结合,形成了一种白光发光二极管(WLED)器件,该器件展现出突出的发光性能。这项工作不仅为钙钛矿发光纳米颗粒的稳定合成提供了一种新方法,而且为其在LED技术中的应用奠定了基础。