Search for: All records

The integration of highly luminescent CsPbBr₃quantum dots on nanowire waveguides has enormous potential applications in nanophotonics, optical sensing, and quantum communications. On the other hand, CsPb₂Br₅nanowires have also attracted a lot of attention due to their unique water stability and controversial luminescent property. Here, the growth of CsPbBr₃nanocrystals on CsPb₂Br₅nanowires is reported first by simply immersing CsPbBr₃powder into pure water, CsPbBr_3−γ X_γ(X = Cl, I) nanocrystals on CsPb₂Br_5−γ X_γnanowires are then synthesized for tunable light sources. Systematic structure and morphology studies, including in situ monitoring, reveal that CsPbBr₃powder is first converted to CsPb₂Br₅microplatelets in water, followed by morphological transformation from CsPb₂Br₅microplatelets to nanowires, which is a kinetic dissolution–recrystallization process controlled by electrolytic dissociation and supersaturation of CsPb₂Br₅. CsPbBr₃nanocrystals are spontaneously formed on CsPb₂Br₅nanowires when nanowires are collected from the aqueous solution. Raman spectroscopy, combined photoluminescence, and SEM imaging confirm that the bright emission originates from CsPbBr_3−γ X_γnanocrystals while CsPb₂Br_5−γ X_γnanowires are transparent waveguides. The intimate integration of nanoscale light sources with a nanowire waveguide is demonstrated through the observation of the wave guiding of light from nanocrystals and Fabry–Perot interference modes of the nanowire cavity.