Synthesis of Ultrasmall Hexagonal NaGdF4: Yb3+Er3+@ NaGdF4: Yb3+@ NaGdF4: Nd3+ Active-Core/Active-Shell/Active-Shell Nanoparticles with Enhanced Upconversion Luminescence

摘要

Currently, enhancing luminescence efficiency of upconversion nanoparticles (UCNPs) has still been a challenging topic in despite of many efforts to improve UC luminescence. Here monodisperse and ultrasmall core-shell-shell nanoparticles, NaGdF4: Yb3+ Er3+ @ NaGdF4: Yb3+ @ NaGdF4: Nd3+ with about 14 nm in diameter were successfully prepared by a facile reactions in high boiling solvents. Dual-model upconversion luminescence in NaGdF4: Yb3+ Er3+ @ NaGdF4 : Yb3+ @ NaGdF4 : Nd3+ core-shell-shell nanoparticles under 980 and 808 nm laser excitation has been demonstrated. And the ultrasmall nanoparticles have the better luminous performance than the core, core-shell nanopariticals. Therefore, these hexagonal core-shell-shell nanoparticles have great superiority as luminescent labeling materials for biological applications. (C) 2017 The Electrochemical Society. All rights reserved.