Encapsulation of CH3NH3PbBr3 Perovskite Quantum Dots in MOF-5 Microcrystals as a Stable Platform for Temperature and Aqueous Heavy Metal Ion Detection.

The stability issue of organometallic halide perovskites remains a great challenge for future research as to their applicability in different functional material fields. Herein, a novel and facile two-step synthesis procedure is reported for encapsulation of CH3NH3PbBr3 perovskite quantum dots (QDs) in MOF-5 microcrystals, where PbBr2 and CH3NH3Br precursors are added stepwise to fabricate stable CH3NH3PbBr3@MOF-5 composites. In comparison to CH3NH3PbBr3 QDs, CH3NH3PbBr3@MOF-5 composites exhibited highly improved water resistance and thermal stability, as well as better pH adaptability over a wide range. Luminescent investigations demonstrate that CH3NH3PbBr3@MOF-5 composites not only featured excellent sensing properties with respect to temperature changes from 30 to 230 °C but also exhibited significant selective luminescent response to several different metal ions in aqueous solution. These outstanding characteristics indicate that the stable CH3NH3PbBr3@MOF-5 composites are potentially interesting for application in fluorescence sensors or detectors.