Influence of Compacting Pressure on the Dielectric Properties of La-modified Bismuth Ferrite Multiferroics Prepared by Rapid Liquid-phase Sintering Method

Abstract

Structure, perovskite phase formation, chemical and phase composition, microstructure, morphology and dielectric properties of the single-phase lanthanum-modified bismuth ferrite multiferroic ceramics obtained by the rapid liquid-phase sintering method under different compacting pressures have been investigated using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermogravimetry/differential thermal analysis and dielectric spectroscopy methods. The temperature and time for an express preparation of the single-phase Bi0.9La0.1FeO3 ceramics with formation of a perovskite structure have been found out. With an increase in the compacting pressure P from 100 to 1100 MPa, the dielectric constant ε′ changes by ∼25% and ∼80% in the low-frequency and ultra-high frequency ranges, respectively. In the low-frequency range, all samples depending on the pressure P demonstrate excellent dielectric behavior with a stable dielectric constant and quite low dielectric loss that make these samples perspective for their possible practical application in microelectronic and spintronic.