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Monodisperse sodium yttrium fluoride corn sticks with hexagonal nanostructure were successfully prepared by a facile and repeatable precipitation transformation method.The phase and morphology of the products were characterized with X-ray diffraction(XRD) and scanning electron microscopy(SEM).The growth mechanism was studied,indicating that the initial generated Y(OH)_3gradually translated into YF_3 and then transformed into corn stick-like H-NaYF_4 nanoparticles owing to the crucial role of fluorine ions in the solution.The up-conversion(UC) luminescence properties of H-NaYF_4:20%Yb~(3+),2%Er~(3+) nanocrystals were discussed.The intensive green emission in the range of 510-570 nm was attributed to the(~2H_(11/2),~4S_(3/2))→~4I_(15/2) transition and the weaker red emission between 640 and 680 nm was originating from the ~4F_(9/2)→~4I_(15/2) transition.
Monodisperse sodium yttrium fluoride corn sticks with hexagonal nanostructure were successfully prepared by a facile and repeatable precipitation transformation method. The phase and morphology of the products were characterized with X-ray diffraction (XRD) and scanning electron microscopy (SEM). The growth mechanism was studied, indicating that the initial generated Y (OH) _3gradually incorporated into YF_3 and then transformed into corn stick-like H-NaYF_4 nanoparticles due to the crucial role of fluorine ions in the solution. The up-conversion (UC) luminescence properties of H (~ 2H_ (11/2), ~2% Er ~ (3+) nanocrystals were discussed. The intensive green emission in the range of 510-570 nm was attributed to the 4S_ (3/2)) → ~ 4I_ (15/2) transition and the weaker red emission between 640 and 680 nm was originating from the ~ 4F_ (9/2) → ~ 4I_ (15/2) transition.