Rare earth β-NaGdF4 fluorides with multiform morphologies: Hydrothermal synthesis and luminescent properties

In this paper, the synthesis of rare earth fluoride beta-NaGdF4 with multiform morphologies via a facile hydrothermal method has been fulfilled. The phases and shapes of the products can be tuned by changing the experimental parameters, including F- source and pH value of mother liquor. The morphologies for the products range from submicrorods, submicrospheres, dumbbell-like nanorods, cobblestone-like particles to aggregates constructed from nanoparticles. The results indicate that F- source and pH value play a critical role in determining the morphologies of the final products. Additionally, we investigate the photoluminescence (PL) properties of Ce3+/Ln(3+) (Ln=Eu, Tb and Dy) codoped down-conversion (DC) and Yb3+/Er3+ (Tm3+, Ho3+) codoped up-conversion (UC) in beta-NaGdF4 host lattices. In the process of DC photoluminescence, energy transfer has occurred. This energy transfer occurs through the energy migration process like S --> Gd3+ --> (Gd3+)(n) --> A (S represents the sensitizer and A represents the activator) and the Gd3+. plays an intermediate role in the process. (C) 2010 Elsevier Inc. All rights reserved.