Preparation of Water-Soluble CsPbBr3 Perovskite Quantum Dot Nanocomposites via Encapsulation into Amphiphilic Copolymers

Water-dispersible and stable fluorescent CsPbBr3 perovskite quantum dots (QDs)-loaded polymeric nanospheres were prepared by an emulsification process. Colloidal CsPbBr3 QDs that were initially prepared in organic solvents were transferred to an aqueous solution by coating with non-ionic amphiphilic polymers, viz., poly(ethyleneoxide)-poly(propyleneoxide)-poly (ethyleneoxide) triblock-copolymer and polyethylene glycolylated hydrogenated castor oil. The polymer-encapsulated CsPbBr3 QDs-loaded nanospheres have an average diameter of similar to 55 nm and they disperse well in aqueous solutions without aggregation or flocculation. The fabricated CsPbBr3 QDs-loaded nanospheres retain their luminescence properties in pure and salt-containing water, which indicates that the polymeric shell of the QDs-polymer nanospheres effectively blocks the diffusion of water and ions into the nanospheres. The results of this study might open many new possibilities for the fluorescent cesium lead halide QDs in a wide variety of applications; for example, they can serve as fluorescent bio-imaging probes.