钙钛矿结构氧化物La0.5Sr0.5CoO3的电导性能研究

Research on Conductivity of Perovskite Oxide LaSrCoO

采用固相反应法制备了La0.5Sr0.5CoO3样品,利用X射线衍射仪和拉曼光谱仪对样品结构进行分析。XRD结果显示,La0.5Sr0.5CoO3样品为单相的立方钙钛矿结构。拉曼光谱图中可看到由氧八面体旋转产生的谱峰以及由Co—O键角及键长振动形成的二级拉曼峰。利用第一性原理的方法计算了La0.5Sr0.5CoO3的能带、态密度与分波态密度,结果表明Sr2+的掺入可以使不导电的钙钛矿型氧化物LaCoO3的导电性发生改变,这对钙钛矿型氧化物LaCoO3的电导特性研究具有指导意义。

La0.5Sr0.5CoO3 samples were prepared by solid-state reaction.The structure of the samples was analyzed by X-ray diffractometer and Raman spectrometer.XRD results indicate that La0.5Sr0.5CoO3 samples are of single-phase cubic perovskite structure.In the Raman spectrum,the peak caused by the rotation of oxygen octahedron and the secondary Raman peak formed by the vibration of Co—O bond angle and length can be observed.The energy band,density of states and partial density of states of La0.5Sr0.5CoO3 are calculated by the first-principles method.The results show that the conductivity of non-conductive pe-rovskite oxide LaCoO3 can be changed by doping Sr2+,which has guiding significance for the study of conductivity of perovskite oxide LaCoO3.