Controlling the Morphology and Size of GdF3:RE3+ (RE = Dy, Tb, and Sm) by pH Value: Growth Mechanism, Energy Transfer, and Luminescent Properties

In this paper, the synthesis of rare earth fluoride GdF3 multiform morphologies via a glutamic acid hydrothermal method has been fulfilled. The size and shape of the products could be tuned just by adjusting the pH values of the initial reaction solutions. The morphologies for the products include spindle-like, peanut-like, submicrometer flowers, and nanoflowers. Additionally, the possible formation mechanism of multiform morphologies was proposed. Furthermore, we systematically investigate the luminescence properties of different lanthanide ions (Dy3+, Tb3+, and Sm3+) in GdF3 host. In the GdF3:Tb3+,Sm3+system, the energy transfer process fromTb3+ to Sm3+ was demonstrated to be resonant type via a dipole–dipole mechanism. Most interestingly, white light and multicolor light have been obtained in Tb3+ and Sm3+ coactivated or Dy3+,Tb3+,Sm3+ tridoped GdF3 phosphors. The results show that the obtained nanophosphors have a promising application in display and lighting fields.