Fully inorganic perovskite quantum dots grown in situ in SiO2 aerogels: green preparation, excellent stability, and their LED applications

Abstract

Perovskite quantum dots have become a research hotspot due to their excellent luminescence properties such as high PLQY and narrow half-wide peaks, but the complex preparation process and poor stability are the main problems affecting their application. In this study, CsPbX₃(X = Br,I) quantum dots were uniformly grown in situ in the inner pores of SiO₂ aerogels by molten salt method in the case of all inorganic ligands, so that perovskite quantum dots can be generated and effectively protected at the same time. The CsPbBr₃@SiO₂ aerogel and CsPbI₃@SiO₂ aerogel composites exhibit highest luminescence intensities at 523 nm and 680 nm respectively, and have narrow half-peak widths (20 nm and 40 nm). At the same time, they have enhanced stability under air, UV lamp and high temperature. After 7 days of exposure to air and UV lamp, the PL strength of the CsPbBr₃@SiO₂ aerogel composites remained 74.5 % and 133 % respectively. Finally, the green and white LED devices have been successfully constructed by laminating CsPbX₃@SiO₂ aerogel composites on the surface of a 460 nm chip. These characteristics have laid a good foundation for the application of LED devices, and at the same time, CsPbX₃@SiO₂ aerogel composites show great potential in luminescence applications.