All-inorganic cesium lead halide perovskite nanocrystals (CsPbX3, X = Cl, Br, or I) present broad applications in the field of optoelectronics due to their excellent photoluminescence (PL), narrow spectral bandwidth, and wide spectral tunability. However, their poor stability limits their practical application. In this work, we successfully use an in situ crystallization strategy for growing and cladding CsPbBr3 perovskite nanocrystals in poly­(vinylidene difluoride) (PVDF). The CsPbBr3 nanocrystals in the as-fabricated CsPbBr3@PVDF composites have an average diameter of 16–18 nm and a strong PL emission (537 nm), with a photoluminescence quantum yield exceeding 30%. In addition, the fabricated CsPbBr3@PVDF composites present improved resistance to heat and water preserving with remarkable optical performance, owing to the effective protection of PVDF. Moreover, the CsPbBr3 nanocrystals generated in PVDF can withstand temperatures up to 170 °C and can be completely immersed in water for 60 days while still retaining high PL intensity, which facilitate the practical application of CsPbBr3 perovskite nanocrystals. These CsPbBr3@PVDF composite films with remarkable optical performances and superior anti-interference ability have broad application prospects in optoelectronics as well as good potential as temperature sensors in mechanical engineering.

Creating highly stable inorganic perovskite nanocrystals (CsPbX 3 , X=Cl, Br and I) with excellent optical performance is challenging because their optical properties depend on their ionic structure and its inherent defects. Here, we present a facile and effective synthesis using a nano confinement strategy to grow Mn 2+ doped CsPbCl 3 nanocrystals embedded in dendritic mesoporous silica nanospheres (MSNs). The resulting nanocomposite is abbreviated as Cs(Pb x /Mn 1x)Cl 3 @MSNs and can serve as the orange emitter for white lightemitting diodes (WLED). The MSN matrix was prepared via a templated solgel technique as monodispersed centerradial dendritic porous particles, with a diamater of around 105 nm and an inner pore size of around 13 nm. The MSN was then utilized as the matrix to initiate the growth of Mndoped perovskite nanocrystals (NCs). The NCs in the resulting composite have an average diameter of 8 nm and a photoluminescence quantum yield (PLQY) exceeding 30%. In addition, the optical properties of the Cs(Pb x /Mn 1x)Cl 3 @MSNs composite can be tuned by varying the Mn 2+ doping level. The resulting composites presented a significantly improved resistance to UV light, temperature, and moisture compared to the bare Cs(Pb 0.72 /Mn 0.28)Cl 3. Finally, we fabricated downconverting white light emitting diodes (WLEDs) by using Cs(Pb x /Mn 1x)Cl 3 @MSNs composite as the orangeemitting phosphor deposited onto UV emitting chips, demonstrating their promising applications in solidstate lighting. This work provides a valuable approach to fabricate stable orange luminophores as replacements for traditional emitters in LED devices.

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A facile and effective templated synthetic strategy to prepare extremely stable CsPbX3 nanocomposites by anchoring CsPbX3 NCs onto silica particles.