Uniform Nanostructured Arrays of Sodium Rare‐Earth Fluorides for Highly Efficient Multicolor Upconversion Luminescence

Abstract

Array of light: Nanostructured arrays of NaMF4 (M=rare earth metal) can be prepared by a hydrothermal method. The arrays consist of nanoparticles with well-controlled morphologies (tubes, disks, or rods), phases (cubic or hexagonal), and sizes (80–900 nm). Multicolor upconversion fluorescence is realized in arrays of NaYF4 codoped with Er3+ and Yb3+ or with Tm3+ and Yb3+ (see picture).