Tysonite type Gd1−yCayF3−y solid solution: hydrothermal synthesis and luminescence properties†
Abstract
The monodisperse submicroplates of Gd1−yCayF3−y solid solution were successfully synthesized by a simple and facile hydrothermal method for the first time. The structure of the as-synthesized Gd1−yCayF3−y was determined to be tysonite-type instead of the usual fluorite-type via a Rietveld refinement method with GSAS. Detailed contrast experiments revealed that the addition amounts of ethylene glycol, calcium chloride, and sodium fluoroborate played critical roles in the formation of the Gd1−yCayF3−y solid solution. Desirable multicolor outputs were successfully realized by doping activator ions (Eu3+, Tb3+, and Dy3+) in the Gd1−yCayF3−y crystals where the Gd3+ ions served as an energy intermediate. Furthermore, the energy transfer from the Gd3+ to Eu3+ ions in the obtained Gd1−yCayF3−y solid solution was more efficient than that in the orthorhombic GdF3.