纳米Y_2O_3:Eu~(3+)(Y_2O_3)粉体的红外光谱研究

采用均相沉淀法和燃烧合成法制备了不同粒径的粉体材料Y2O3:Eu3+,着重研究了样品的红外光谱,探讨了纳米晶Y2O3:Eu3+与同质微米材料相比的微观结构的变化.研究发现,波数位于563 cm-1的Y(Eu)—O键的吸收峰校正高度和面积对于纳米级粒径的粉体材料随着颗粒的减小而减小,而对于同质微米材料却相反.经分析认为:Y(Eu)—O键的吸收峰校正高度和面积由Y(Eu)—O键的平均键长和Y(Eu)—O键振动态数目这两个因素决定.对于微米粉体Y(Eu)—O键长的变化起主要作用,而对于纳米粉体由于不饱和键和悬空键的形成,Y(Eu)—O键振动态数目的变化起主要作用.

Infrared spectra research of nanocrysalline Y2O3:Eu3+ (Y2O3)

Different grain sizes of Y2O3:Eu3+(Y2O3) powder have been prepared by the homogeneous precipitation technique and the glycine-nitrate solution combustion synthesis.The infrared absorption spectra of the samples are studied.It is found that there are obvious differences of local structure between the nanometer and the micron crystalline powders.We found firstly that the correction height and the correction area of the absorption peak of the Y(Eu)—O bond at 563 cm-1 increase with the size of the nanocrystalline until the particle size exceeds 100 nm in the opposite way.We believe that the correction height and the area of the absorption peak of the Y(Eu)—O bond are determined from two factors: the average bond-length and the number of the vibrating-running states of the Y(Eu)—O bond.For the micron scale powders,the increase of the correction height and the area of the absorption peak with the decrease of the grain size is due to the increase of the average length of Y(Eu)—O.But for the nanocrystalline,the decrease of the number of Y(Eu)—O bond in vibrating-running states is the main factor due to the mini-scale effect and the increase of the hanging bonds.