【作者】 刘建伟； 罗飞； 周德凤； 孟健；

【Author】 Jianwei Liu~1,Fei Luo~1,Defeng Zhou~(1,*),Jian Meng~(2,*) 1 School of Chemistry and Life Science,Changchun University of Technology,Changchun 130012,P.R,China; 2 State Key Laboratory of Rare Earth Resources Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,P.R.China

【机构】 长春工业大学化学与生命科学学院； 中国科学院长春应用化学研究所稀土资源利用国家重点实验室；

【摘要】 采用溶胶凝胶法合成SiO₂含量为0.05%（ω,质量分数）的Ce_0.8Nd_0.2O_1.9（NDC）粉体（NDCSi）,将0-2.0%（x,摩尔分数）的MgO和FeO_1.5分别添加到NDCSi粉体中,经10 MPa压片后于1300℃烧结6 h.采用X射线衍射（XRD）、拉曼光谱（Raman）和场发射扫描电子显微镜（FE-SEM）对样品进行结构表征.采用交流阻抗谱（AC）测试样品导电性能.结果表明:所有样品均呈现单一立方萤石结构.MgO和Fe₂O₃掺杂于NDCSi体系,均可提高材料的致密度,降低烧结温度,提高材料的晶界电导率和总电导率,掺杂MgO或Fe₂O₃样品的相对密度（>93%）高于NDC或NDCSi（约86%）,有效促进了样品致密化.NDCSi+0.5FeO_1.5和NDCSi+2.0MgO在550℃时总电导率是NDCSi总电导率的5.7和2.6倍.MgO和Fe₂O₃均具有烧结助剂和晶界清除剂的双重作用,但清除杂质SiO₂的机制不同.更多还原

【Abstract】 The precursor powder of Ce_0.8Nd_0.2O_1.9（NDC） containing 0.05%（mass fraction,ω） SiO₂ as an impurity（NDCSi） with 0-2.0%（molar fraction,x） MgO or FeO_1.5doping was prepared by the sol-gel method.After pressed under 10 MPa.the samples were sintered at 1300℃for 6 h.Their structures were characterized by X-ray diffraction（XRD）,Raman,field emission scanning electron microscopy（FE-SEM）.Electrical conductivity of the pellets was measured using AC impedance spectroscopy.The results showed that all the samples exhibit a cubic thorite structure.MgO or Fe₂O₃ addition could increase the density,lower sintering temperature,increase the grain boundary and total conductivity of the NDCSi.Relative density of the samples doped FeO_1.5or MgO（>93%） is higher NDC or NDCSi（about 86%）,which are more effective in promoting densification.The toll conductivity of NDCSi+0.5FeO_1.5 and NDCSi+2.0MgO areby 5.7 and 2.6 times comparing with that of NDCSi at 550℃.MgO or Fe₂O₃ is shown to be an effective sintering aid.as well as a grain-boundary scavenger with different mechanisms of scavenging effect.更多还原