Self-assembly and multicolor emission of core/shell structured CaWO_4:Na~+ /Ln~(3+) spheres

摘要

A novel core/shell CaWO_4 microsphere co-doped with Na~+ and Ln~(3+) (Ln = Dy, Tb, Sm, Eu) was successfully prepared by the self-assembly of 8.5 nm particles, and shows a unique multicolor emission in the visible region when excited by single-wavelength light.rnThe self-assembly of nanocrystals of specific morphology has drawn great attention because of their interesting properties and many applications. To fabricate the nanodevices of the future, nanocrystals have to be taken as the building blocks for the nanoarchitectures. There have been plenty of reports on the synthesis of nanocrystals in which self-assembly appears to be more effective for assembling the nanocrystals into two or three dimensional superstructures, and therefore becomes an essential part of the nanotechnology. It is well documented that further understanding of self-assembly phenomena is fundamentally important, which may help to translate the chemical language of molecular self-assembly into the organization of various nanocrystals for certain functions.