Structural, Magnetic and Dielectric Properties of Bi0.9Re0.1FeO3(Re = La, Sm, Gd and Y)

Abstract

With a view to understand the influence of rare earth ion doping on the structural, magnetic and dielectric properties of bismuth ferrite, a series of samples were prepared by the solidstate reaction method. After characterizing the samples with XRD and SEM studies, the magnetic and dielectric measurements were carried out. It is interesting to note that the two impurity phases, viz., orthorhombic Bi 2 Fe 4 O 9 and cubic Bi 25 FeO 40 observed in undoped bismuth ferrite are found to vanish with rare earth doping. Further, the remnant magnetization (M r ) values are found to increase with increasing ionic radii of dopant rare earth ion. Interestingly, among all the samples, La doped BiFeO 3 sample is exhibiting negative magnetization at low temperatures. The dielectric constant is found to exhibit two transitions above room temperature. Efforts have been made to explain the observed structural, magnetic and dielectric behaviours of the materials.

Elastic and Attenuation Studies of Some Rare Earth Substituted Multiferroic Bismuth Ferrites

“…The experimentally observed and calculated Rietveld refined patterns of one representative sample (BGFO compound) along with the difference in both the patterns are shown in Figure 1b and the refined crystallographic data are given in Table 1. The results are in good agreement with those available in the literature [5,20] and no structural changes have been observed. There is an almost linear variation of the lattice parameters a, b, and c and the variations are in accordance with the well-known lanthanide contraction phenomenon.…”

“…There is an almost linear variation of the lattice parameters a , b , and c and the variations are in accordance with the well‐known lanthanide contraction phenomenon. [ 5 ]…”

“…[3,4] In fact, the bulk BFO shows multiferroic properties with high ferroelectric transition temperature (1100 K) and weak AFM Neel temperature (643 K). [5] Recent reports suggest that BFO can be used as photocatalytic material for the significant degradation of the industrial dyes. [6] Despite several advantages of these materials, a superimposed spiral spin structure with an incommensurate long wavelength of period 620 Å cancels the macroscopic magnetization in bulk BiFeO 3 .…”

“…[13] Furthermore, although bismuth ferrites and several of their doped compounds are having multiferroic behavior, work only on ferromagnetic and ferroelectric properties is reported earlier. [5,6,14] In fact, ferroelastic behavior is the third ferroic property and is equally important and essential for the characterization of multiferroics. Moreover, no work on ferroelastic or at least on elastic behavior of multiferroics in general and bismuth ferrite-based multiferroics in particular is available in the literature.…”

Applying the FMR Technique to Analyzing the Influence of Nitriding on the Magnetic Properties of Steel

“…Increasing in temperature destroys antiferromagnetic ordering and magnetization is enhanced. Similar behavior of magnetization with temperature relation was observed in other Fe-containing materials [18], where increase in the magnetization was explained by the creation of Fe 2+ ions in the structure built of Fe 3+ .…”