Synthesis, Structural Characterization, Dielectric and Piezoelectric Properties of Multiferroic Double-perovskite Bi2FeMnO6 Ceramics

National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China

Adv. Mater. Lett., 2019, 10 (12), pp 874-879

DOI: 10.5185/amlett.2019.0008

Publication Date (Web): May 18, 2019

Copyright © IAAM-VBRI Press

Corresponding author: E-mail: xhzhu@nju.edu.cn

Abstract

Double-perovskite structured multiferroic Bi₂FeMnO₆ (BFMO) ceramics synthesized via solid-state reaction route at 880^oC for 3 h, crystallized in a distorted rhombohedral structure with R3c space group. Their lattice parameters in the hexagonal system were determined to be a = 5.571 Å and c = 13.191 Å. SEM images show that the BFMO ceramic grains exhibit spherical morphology with an average size of 6.70 mm. Their atomic ratio of Bi:Fe:Mn was determined to be 2.07:1.02:1.00, close to the nominal value of 2:1:1. Raman spectra have verified the vibrational frequencies in the BFMO ceramics, and only 11 Raman active modes are observed. The less observed Raman modes in the BFMO ceramics compared with the theoretical group analyses, can be ascribed to the small correlation field splitting of the ceramic samples due to their polycrystalline nature. BFMO ceramics exhibit almost frequency-independent dielectric behavior in a frequency range of 500 - 10⁶ Hz at room temperature. Their dielectric constant and dielectric loss were measured to be 700 and 0.03 at 10⁶ Hz, respectively. The piezoelectric moduli d₃₃ of the poled BFMO ceramics was measured to be 56 pC/N, which is two times larger than that reported for BiFeO₃ thin film (d₃₃ ≅ 25 pC/N). © VBRI Press.

Keywords

Double perovskite oxides, Bi₂FeMnO₆ multiferroic ceramics, Raman spectra, dielectric and piezoelectric properties, microstructural characterization