| YVO4: Eu3+nanophosphors have been known for its high luminescence intensity,color purity, photoluminescence quantum yield and good radiation stability. It hasattracted much attention and became a research focus because of these advantages. Inthis work, the preparation and photoluminescence properties of YVO4: Eu3+nanostructure phosphors were studied, and the following results were obtained:(1) The YVO4: Ba2+and YVO4: Sr2+precursors were synthesized by asolvothermal method and codoped Eu3+by ion exchange method. The surface Eu3+ion diffused into the crystal lattice via a annealing process. In comparison with thoseof YVO4: Eu3+nanocrystals, the luminescent intensity of YVO4: Eu3+, Ba2+andYVO4: Eu3+, Sr2+are greatly enhanced, and a quenching behavior of both Ba2+andSr2+doping amounts has been found in the YVO4: Eu3+, Ba2+and YVO4: Eu3+, Sr2+phosphors, respectively. It was observed that Ba2+and Sr2+dopants greatly enhancedboth the VO34-to Eu3+charge transfer intensity and the intrinsic excitation intensity ofthe Eu3+ions. The influence of annealing on the luminous performance of YVO4:Eu3+, Ba2+and YVO4: Eu3+, Sr2+particles was also investigated in this paper. Theemission intensity of the annealed sample is much stronger than the sample withoutannealing.(2) The YVO4: Eu3+, Bi3+, Ba2+nanophosphors were synthesized by asolvothermal method and the YVO4: Eu3+, Ba2+@YVO4: Eu3+, Bi3+core-shellstructure nanophosphors synthesized by a two-step solvothermal method. Theinfluences of codoping Bi3+and Ba2+ion into YVO4: Eu3+nanophosphor wereinvestigated. The average grain sizes of the samples are11~15nm. With the ratio ofcore and shell increased, the average grain sizes became larger. When doped with Bi3+,the maximum of the excitation band shifts to longer wavelength, and the excitationband broadened, but when codoped Bi3+and Ba2+into YVO4: Eu3+, the luminescenceproperties decreased. The maximum of the integral area of excitation peaks wasobtained when controlled the ratio of core and shell as4. |
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