Temperature-dependent impedance spectroscopy of La0.8Sr0.2FeO3 nano-crystalline material

International Symposium on Current Progress in Functional Materials

Kafa, C.A.^1 ; Triyono, D.^1 ; Laysandra, H.^1

Department of Physics, Faculty of Mathematics, Natural Sciences Universitas Indonesia, Kampus UI Depok, Depok

16424, Indonesia^1

关键词: Dopant concentrations;    Electrical conductivity;    Electrical permittivity;    Emerging agglomerations;    Impedance spectroscopy;    Orthorhombic perovskite;    Structural modifications;    Temperature dependent;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/188/1/012027/pdf
DOI  :  10.1088/1757-899X/188/1/012027

来源: IOP

【 摘 要 】

LaFeO3is a material with perovskite structure which electrical properties frequently investigated. Research are done due to the exhibition of excellent gas sensing behavior through resistivity comparison from the p-type semiconductor. Sr doping on LaFeO3or La1-xSrxFeO3are able to improve the electrical conductivity through structural modification. Using Sr dopant concentration (x) of 0.2, La0.8Sr0.2FeO3nano-crystal pellet was synthesized. The synthesis used sol-gel method, followed by gradual heat treatment and uniaxial compaction. XRD characterization shows that the structure of the sample is Orthorhombic Perovskite. Topography of the sample by SEM reveals grain and grain boundary existence with emerging agglomeration. The electrical properties of the material, as functions of temperature and frequency, were measured by Impedance Spectroscopy method using RLC meter, for temperatures of 303-373K. Through the Nyquist plot and Bode plot, the electrical conductivity of La0.8Sr0.2FeO3is contributed by the grain and grain boundary. Finally, the electrical permittivities of La0.8Sr0.2FeO3are increasing with temperature increase, with the highest achieved when measured at 1 kHz frequency.