Hydrothermal synthesis of NaY(WO_4)_2:Tb~(3+) powders with assistance of surfactant and luminescence properties

摘要

NaY(WO_4)_2:Tb~(3+) powders with different sizes and morphologies were synthesized by the hydrothermal process. The surfactants and reaction times have obvious effects on sizes and morphologies of samples. When there is the addition of an equimolar combination of oleic acid and oleylamine and the reaction time of 10 h, uniform morphology of octahedron can be formed. As indicated by the FTIR spectra, the enhanced adsorption of oleic acid in the presence of oleylamine leads to the good formation of octahedral NaY(WO_4)_2:Tb~(3+) powders. Surfactants will selectively absorb on the surface of the growing particles via physical and chemical effects, which leads to different growing rates along corresponding directions and induces the formation of octahedral morphology. Under the ultraviolet excitation, NaY(WO_4):Tb~(3+) powders show dominant green emission originating from the ~5D_4 → ~7F_5 transition of Tb~(3+) ions.