关键词: 核壳, Gd₂O₃Eu^3＋, 发光材料, 表面效应

Gd₂O₃:Eu^3＋@Y₂O₃ core-shell structural luminescence nanomaterials were prepared by homogeneous precipitation method. XRD patterns show that the sample calcined at 800 ℃ is cubic phase Gd₂O₃, and the crystal grows well, after coated with Y₂O₃, the diffraction peak position of Gd₂O₃ is not changed, while with the increase of the coating thickness, cubic phase Y₂O₃ diffraction peaks appear. In FTIR spectra, it is observed that Gd—O, Y—O stretching vibration absorption peaks increase with decreasing the coating thickness, this reason is that when the coating thickness is suitable, the dangling bonds on the particle surface are less, which results in Gd(Eu,Y)—O bonds increase. SEM images indicate that the samples before and after coated are all in sphere shape. XPS analysis further proves that the Y₂O₃ is coated on the surface of Gd₂O₃:Eu^3＋. Photoluminescence properties show that coating the Y₂O₃ host with different thickness on the surface of Gd₂O₃:Eu^3＋ nanoparticles, the Eu^3＋ characteristic red emission can be observed. And when the coating thickness is suitable, that is Gd₂O₃:Eu^3＋/Y₂O₃ ratio of R＝4∶1, the luminescence intensities of core-shell particles are higher than that of the Gd₂O₃:Eu^3＋ core nanocrystals, it is thought that the core-shell samples decrease the negative effects of nanoparticles on the luminescence properties.

Key words: core-shell, Gd₂O₃Eu^3＋, luminescence material, surface effect