Gd2O3:Eu3+@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:Eu3+.Photoluminescence properties show that coating the Y2O3 host with different thickness on the surface of Gd2O3:Eu3+ nanoparticles, the Eu3+ characteristic red emission can be observed.And when the coating thickness is suitable, that is Gd2O3:Eu3+/Y2O3 ratio of R=4: 1, the luminescence intensities of core-shell particles are higher than that of the Gd2O3:Eu3+ core nanocrystals, it is thought that the core-shell samples decrease the negative effects of nanoparticles on the luminescence properties.%采用均相沉淀法制备了均匀球形的Gd2O3:Eu3+@Y2O3核壳结构纳米发光材料.XRD结果表明经过800℃焙烧后样品为立方晶系的Gd2O3,并且晶体发育良好,包覆Y2O3之后Gd2O3的衍射峰位置无明显变化,但随着包覆厚度的增加,出现了立方晶系Y2O3的衍射峰.FTIR谱图观测到了Gd-O,Y-O伸缩振动吸收峰,随着包覆厚度的减少吸收峰增强,认为当包覆层的厚度适当时,颗粒表面的悬空键(断键)变少,Gd(Eu,Y)-O键增多所致.SEM表明包覆前后样品为均匀分散的球形结构.XPS分析进一步证明了表面包覆上了Y2O3.荧光光谱表明:纳米Gd2O3:Eu3+表面包覆不同厚度的基质Y2O3后,均观测到Eu3+离子的特征红光发射,当包覆厚度R=4:1时的发光强度比未包覆的Gd2O3:Eu3+增强,认为核-壳型样品降低了纳米Gd2O3:Eu3+的表面效应给发光强度带来的负面影响.
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