Effects of the penetration temperature on structure and electrical conductivity of samarium modified BaTiO_3 powders  

作　　者：付东升 郝素娥 李佳龙 强亮生 

机构地区：[1]Department of Chemistry,Harbin Institute of Technology

出　　处：《Journal of Rare Earths》2011年第2期164-167,共4页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (20571020)

摘　　要：Gaseous penetration technique was adopted to improve the electrical conductivity of BaTiO3 powders and the effects of penetration temperature on the structure and electrical conductivity of Sm-modified BaTiO3 powders were studied.It was observed that the penetration of Sm made the resistivity of BaTiO3 powders decrease with the increase in the penetration temperature and decreased to the lowest point of 4.20×102 ？·m when the penetration temperature was 950 oC.The relationship curve of the temperature and resistivity of the samples was also established preliminarily to get the mathematical expression by the fitting method.Through X-ray diffraction （XRD） analysis,the new phases of Sm2O3 and Ba4Ti2O27 were detected.It was indicated that intricate reactions related to Sm took place during the penetration process and led to the Ti-rich state of the system.The Fourier transform infrared （FTIR） spectrum illustrated that the bonds of Ti–O octahedron was strengthened by substitution of Sm3＋ at Ti4＋ sites,which led to the growth of Ti：Ba ratio.The analysis results of scanning electron microscopy （SEM） indicated that the particle size of Sm-modified BaTiO3 powders progressed with the penetration temperature increasing.Gaseous penetration technique was adopted to improve the electrical conductivity of BaTiO3 powders and the effects of penetration temperature on the structure and electrical conductivity of Sm-modified BaTiO3 powders were studied.It was observed that the penetration of Sm made the resistivity of BaTiO3 powders decrease with the increase in the penetration temperature and decreased to the lowest point of 4.20×102 ？·m when the penetration temperature was 950 oC.The relationship curve of the temperature and resistivity of the samples was also established preliminarily to get the mathematical expression by the fitting method.Through X-ray diffraction （XRD） analysis,the new phases of Sm2O3 and Ba4Ti2O27 were detected.It was indicated that intricate reactions related to Sm took place during the penetration process and led to the Ti-rich state of the system.The Fourier transform infrared （FTIR） spectrum illustrated that the bonds of Ti–O octahedron was strengthened by substitution of Sm3＋ at Ti4＋ sites,which led to the growth of Ti：Ba ratio.The analysis results of scanning electron microscopy （SEM） indicated that the particle size of Sm-modified BaTiO3 powders progressed with the penetration temperature increasing.

关 键 词：gaseous penetration BATIO3 SAMARIUM electrical conductivity rare earths 

分 类 号：TB383.3[一般工业技术—材料科学与工程]