Preparation, structural analysis and dielectric properties of Bi$_{𝑥}$La$_{1-𝑥}$FeO3 perovskite

Pramana

S A Patil¹  M B Kothale¹  P B Joshi²  S B Kulkarni²  K K Patankar¹  V L Mathe1¹ 

[1] Department of Physics, Shivaji University, Kolhapur 416 004, India$$;Department of Physics, P.G. Center, Shivaji University, Solapur, India$$

关键词: Perovskite;    X-ray diffraction;    dielectric constant;    ac conductivity.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

Rare earth element substituted bismuth ferrites (BiFeO3) are of enormous importance as magnetoelectric materials. The polycrystalline samples of Bi𝑥La1-𝑥FeO3 (𝑥=0, 0.2, 0.4, 0.6, 0.8) were prepared by solid-state reaction using standard ceramic method. The single-phase formation of these compounds was confirmed by X-ray diffraction (XRD) studies. The samples with 𝑥 = 0, 0.2, 0.4, 0.6 are found to be orthorhombic while the sample with 𝑥 = 0.8 is triclinic. The dielectric constant (𝜖') and dissipation factor (tan 𝛿) were measured in the frequency range 100 Hz to 1 MHz at room temperature and as a function of temperature at certain fixed frequencies (1 kHz, 10 kHz, 100 kHz, 1 MHz). All the samples showed dielectric dispersion. The dielectric constant with temperature shows a broad peak; the peak temperature shifts with frequency which reflects the relaxor-type behavior. The peak above 600 K in the measured temperature range corresponds to antiferromagnetic ordering temperature (Néel temperature). The broadness of the peak changes with composition. The ac conductivity as well as 𝜖' are found to be maximum for the sample 𝑥 = 0.2 at room temperature.

【 授权许可】

Unknown