Dual-emission CPB@SMSO@SiO₂ composites with tunable afterglow through energy transfer

Afterglow materials face limitations in color variety, low luminosity, and stability. Thus, developing materials with adjustable afterglow color, increased photoluminescence (PL) intensity, and enhanced stability is crucial. This paper reports the fabrication of a series of core-shell composites, CPB@SMSO@SiO₂, which combine Sr₂MgSi₂O₇: Eu²⁺, Dy³⁺ (SMSO) and lead halide perovskite quantum dots (CsPbBr₃/CPB PeQDs) through a process involving in-situ growth and hydrolytic coating. The SMSO in the composite can absorb 365 nm UV light and then emit 470 nm light, which can be absorbed by the CsPbBr₃ PeQDs, resulting in an overall increase in the PL intensity of the composite. The afterglow color can be turned from green to blue by adjusting the ratio of SMSO and CsPbBr₃. Furthermore, the stability of the composites is improved by the SiO₂ shell layer formed by hydrolysis of tetramethyl orthosilicate (TMOS). This study presents an opportunity to develop innovative afterglow materials.