Simultaneous encapsulation and structural behavior of high-utility CsPbX3 quantum dots in 3D dendritic mesoporous silica nanospheres

Cesium lead halide (CsPbX 3 ) perovskite quantum dots (PQDs) instability is solved by sealing them in 3D form double-layered mesoporous silica nanospheres (3D-MSNs) with uniform particle size. When compared to other commercial 2D mesoporous silica materials, 3D-MSNs can better encapsulate PQD precursors within their pores. After introducing CsX and PbX 2 into 3D-MSN pores, calcination provides simultaneous production of CsPbX 3 and coverage for outer-layer 3D-MSN pores, resulting in the formation of a water and light-resistant CsPbX 3 @3D-MSNs composite material. The growth mechanism of PQDs inside 3D-MSNs and their thermal phase structure behavior are deeply studied. Heating and cooling at 25–350 °C affects the crystal phase of PQDs (δ, α, β, and γ) and their photoluminescence properties. The CsPbX 3 @MSNs composite material exhibits high stability and dispersity, making it suitable for light-emitting diodes and stretchable, self-healable, luminescent thin films. • Perovskite quantum dots were encapsulated into 3D mesoporous silica nanospheres. • Sintering could form and trap perovskite QDs inside the 3D-MSNs pores concurrently. • Thermal phase change of the perovskite crystals in the 3D-MSNs has been studied. • Perovskite crystal change from δ, α, β, to γ phase during synthesis was confirmed. • CsPbX 3 @3D-MSNs are applicable for LED devices and luminescent thin films.