Controlled synthesis and luminescence properties of GdF3 with different crystalline phases and morphologies

Abstract

GdF₃ with raisin-like particles, plates with dots in their centers, peanut-like particles and spherulite-like particles have been synthesized via a simple hydrothermal method with tartaric acid as an additive, by simply modulating the pH values and H₂O/ethanol ratio of the system. The possible formation mechanisms of the particles obtained in mixed solvents and pure water are proposed based on a series of time-dependent experiments. Both hexagonal and orthorhombic phases were obtained and the factors influencing the phase transitions are discussed in detail. The luminescence properties prove that the GdF₃ particles are excellent host lattices. Under ultraviolet excitation, GdF₃:Eu³⁺ particles exhibit strong red emission corresponding to the ⁵D₀ → ⁷F₁ transition of the Eu³⁺ ions. Furthermore, the dependence of GdF₃:Eu³⁺ luminescence performances on different morphologies and phases are discussed in the present work.