Solvothermal synthesis and tunable luminescence of Tb3+, Eu3+ codoped YF3 nano- and micro-crystals with uniform morphologies

Tb3+, Eu3+ codoped YF3 nano- and micro-crystals with the morphologies of ellipsoid-like nanoplate, spindle, sandwich-structural rhombus and nanoaggregate were synthesized through a solvothermal method. The morphologies of the prepared products can be tailored by controlling the volume ratio of ethylene glycol (EG) to H2O, solvent type or the reaction time. A possible formation mechanism of the sandwich-structural rhombus like YF3 phosphor was proposed. The emitting colors of YF3:Tb3+,Eu3+ phosphors can be easily tuned from yellowish green, yellow to orange by increasing Eu3+ concentration. The energy transfer from Tb3+ to Eu3+ in YF3 phosphors was studied. It was found that the interaction type between Tb3+ and Eu3+ is electric dipole–dipole interaction.