Transparent Luminescent Perovskite–Poly(methyl methacrylate) Composites with Water-Resistant and Air-Stable Properties

Encapsulation of all-inorganic perovskite quantum dots (QDs) with polymers is a convenient and effective strategy to improve their stability against air and water. Herein, poly(methyl methacrylate) (PMMA) was employed to encapsulate perovskite QDs, and highly transparent perovskite-PMMA composites were fabricated via a facile solvent evaporation method. Photoluminescence measurements reveal that the PL emission peak positions of all composites shift by no more than 9 nm relative to those of the corresponding perovskite QD solutions, and the photoluminescence quantum yield is maintained in the range of 39.8-59.6%. Moreover, the composites exhibit outstanding stability in both air and water: the spectral shape and intensity remain virtually unchanged after 40 days of exposure in air, and the luminescence intensity is preserved above 82.9% of the initial value after 30 days of immersion in water. These results suggest that perovskite-PMMA composites hold great promise for applications in optical lighting, anti-counterfeiting encryption, and other optical functional materials.