Sintering- and water-resistant perovskite quantum dots supported by inorganic materials for enhanced luminescence

Metal halide perovskite quantum dots (MHPQDs) have attracted intensive interest because of their unique optoelectronic properties. Their undesirable degradation upon exposure to humidity and/or heat, however, poses a dear challenge for the practical applications. Herein we report a facile strategy to develop sintering-resistant MHPQDs, e.g. CsPbBr₃, by localizing them on the surface of inorganic support such as hydroxyapatite (HAP). The chemical interaction between CsPbBr₃ quantum dots (QDs) and HAP support originates from the occupation of Br vacancies in CsPbBr₃ by the –O⁻ on the surface of HAP support, which not only stabilizes the small particle sizes (∼2.2 nm) of CsPbBr₃ QDs upon high-temperature (up to 400 °C) calcination but also greatly enhances its photoluminescence emission intensity by about 150 times. Interestingly, the supported CsPbBr₃ QDs decorated by cetyltrimethylammonium bromide can further produce water-resistant CsPbBr₃@CsPb₂Br₅ QDs. The obtained sintering-resistant hydroxyapatite-supported CsPbBr₃@CsPb₂Br₅ QDs can be used to fabricate green light emitting diodes (LED) devices with high luminous intensity for medicolegal identification, flexible luminescence film for display, and potential fluorescent label for bioimaging/biosensing applications. This work demonstrates a novel strategy to design and develop robust all-inorganic QDs composites that may find wide applications in diverse environmental conditions, including high temperature and/or high humidity.