Magenta-Emitting Cesium Lead Halide Nanocrystals Encapsulated in Dimethicone for White Light-Emitting Diodes

Recently, more attention has been paid for the research of CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) owing to their tunable luminescence characteristics and ultrahigh photoluminescence quantum yields. However, there are still several problems, such as lack of polychromatic cofluorescence, relatively high hot-injecting temperature, instantaneous reactive time, inert atmosphere protection, and poor anti-anion exchange characteristics, which need to be solved urgently for their further applications in solid-state lighting. Herein, a microwave-assisted method is performed to synthesize perovskite NCs without inert atmosphere at room temperature. Polychromatic magenta-emitting CsPb(Br,Cl)(3):Mn2+ (CPBCM) NCs are achieved by controlling accurately the ratio of excitonic and manganese ion emissions. To further encapsulate the NCs with dimethicone, the characteristics of luminous decay and thermal quenching are improved, originating from the formation of CsPb(Br,Cl)(3):Mn2+ pdimethicone (CPBCMD) nanostructures. Finally, a white light-emitting diode (WLED) with distinct anti-anion exchange characteristic is achieved by combining the nanostructures with CsPbBr3@dimethicone NCs, which presents a promising scheme to implement all-perovskite NC-based WLEDs.