Silica Aerogel-Encapsulated CsPbX₃ Nanocrystals: A Robust Platform with Enhanced Optical Performance for...

All-inorganic halide perovskite nanocrystals (NCs) exhibit outstanding optoelectronic properties, yet their practical applications in wide-color-gamut displays are severely constrained by inherent stability. Here, we developed a robust encapsulation strategy for CsPbX₃ NCs using low-cost silica aerogels (AGs) through an improved low-temperature molten-salt sintering method. During sintering, the aerogel pore structure partially collapses, mechanically sealing the NCs within a rigid inorganic framework. Subsequent alkaline treatment leads to the in situ formation of a PbBr(OH) secondary shell, providing an additional chemical protection layer. Owing to this dual-encapsulation architecture, the resulting CsPbBr₃@AGs(OH) composites exhibit intense green emission with a high photoluminescence quantum yield of 91%, together with remarkable resistance to moisture, heat, and high-intensity irradiation. Notably, the corresponding polymer film retained 97.6% of its initial luminance after 1000 h of continuous blue-light exposure at 300W/m². By extending this strategy, blue- and red-emitting CsPbX₃@AGs composites covering the 443-659 nm range are achieved, enabling an ultrawide-color-gamut coverage of 132.85% NTSC and 99.2% Rec.2020. This work provides a universal, low-cost, and scalable encapsulation platform that simultaneously delivers an excellent optical performance and long-term stability, paving the way for next-generation display applications.