Phase control of upconversion nanocrystals and new rare earth fluorides though a diffusion-controlled strategy in a hydrothermal system

Abstract

Here we report a general hydrothermal technology to obtain well-known rare earth fluorides involving β-NaYF₄:Yb, Er/Tm and β-NaGdF₄:Yb, Er/Tm upconversion nanocrystals, one new polymorph of γ-REF₃ (RE = Eu–Tm, Y) and hexagonal LiREF₄ (RE = Nd–Lu, Y) colloidal nanocrystals.