| Abstract: | In this paper,we report for the first time the controlled synthesis of lanthanide ion(Ln~(3+))-doped tetragonal-phase Na_3Zr F_7 nanocrystals(NCs)via a high-temperature co-precipitation approach.The as-synthesized Na_3Zr F_7 NCs are systematically studied by utilizing the XRD,TEM as well as high-resolution photoluminescence(PL)spectroscopy.The morphology and size for the as-synthesized Na_3Zr F_7 NCs can be finely controlled by changing the experimental parameters such as the amount of precursor,solvent ratio,reaction temperature and time.By utilizing the red-emitting Eu~(3+)ion as an efficient optical/structural probe,the successful hetero-valence doping of Ln~(3+)activators in the lattices of Na_3Zr F_7 NCs is well-established regardless of their different valences and radii between host Zr~(4+)ion and Ln~(3+)dopant.As a result,intense upconversion(UC)luminescence(UCL)ranging from UV to visible and to NIR spectral regions can be readily achieved after the doping of typical UCL couples of Yb~(3+)/Er~(3+),Yb~(3+)/Tm~(3+)and Yb~(3+)/Ho~(3+)into the lattices of Na_3Zr F_7 NCs when excited by using a 980-nm NIR diode laser. |
