Structural and impedance analysis of Co-doped SrTiO3 perovskite

3rd International Meeting for Researchers in Materials and Plasma Technology; 1st Symposium on Nanoscience and Nanotechnology

物理学;材料科学

Echeverri, E.^1 ; Arnache, O.^1

Universidad de Antioquia, Medellin, Colombia^1

关键词: Co-doped;    Electrical conductivity;    Impedance analysis;    Impedance spectroscopy measurements;    Low-frequency;    Morphology and composition;    Perovskite-type structure;    Polycrystalline samples;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/687/1/012040/pdf
DOI  :  10.1088/1742-6596/687/1/012040

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

SrTi1-xCoxO3 (0.2≥x≥0) polycrystalline samples were prepared by solid-state reaction. X-ray diffraction (XRD) analysis shown the perovskite type structure is conserved for all samples without impurities. A small increase in the lattice parameters were observed for x≥0.05. Morphology and composition were analysed by scanning electron microscopy (SEM- EDX). Impedance spectroscopy measurements form 50Hz to 1MHz were made at different temperatures (25-400°C). The spectra were analysed by Z' vs Z'' plots, which reveal 3 contributions associated to electrodes, grain boundary and grain. From the fits the frequency f) and times relaxation (τ) of the grain were estimated, with values of f∼15KHz and τ∼67μs for 20% Co samples at RT. A dispersion in the permittivity Ε∗ at low frequency (