In-situ synthesis of highly stable CsPbBr3/PbBrF composite nanocrystals induced by Hydrofluoric acid

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2022-02, Vol.430, p.132680, Article 132680
• Main Authors: Lou, Sunqi, Si, Shuaichen, Huang, Lin, Gan, Weijiang, Lan, Bang, Zhang, Jinhui, Li, Manrong, Xuan, Tongtong, Wang, Jing
• Format: Article
• Language: English
• Subjects: Composites; Nanocrystals; Perovskite; Stability
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2021.132680

•A aqueous synthesis method is adapted for CsPbBr3/PbBrF composites NCs.•The CsPbBr3 NCs are transformed from CsPb2Br5 NCs by Hydrofluoric acid.•The CsPbBr3/PbBrF composite NCs show excellent stability. All inorganic lead cesium halide perovskites (CsPbX3, X  = Cl, Br, I) nanocrystals (NCs) are supposed to be promising luminescent-converting materials for next-generation displays, on account of their excellent optical and photoelectric properties, facile synthesis, and low cost. However, the inherent poor stability hinders their implementation in practical applications. Here, we present a simple cooperative strategy for the synthesis of stable green perovskite composite luminophore powders. In a typical cooperative process, HF leads to the formation of PbBrF framework in which the green-emitting CsPbBr3 NCs that are transformed from the non-emitting precursors CsPb2Br5 NCs by hydration, are simultaneously embedded in. The obtained CsPbBr3/PbBrF composites NCs maintain photoluminescence quantum yield (∼ 30%) and narrow band emission (∼ 22 nm). Additionally, benefiting from the PbBrF framework with good thermal diffusivity and stability, CsPbBr3/PbBrF composite NCs show excellent stability to heat, radiation, and polar solvents, which can be used as promising green luminescent-converting materials in the next-generation displays.