Dielectric, electrical conduction and magnetic properties of multiferroic Bi0.8Tb0.1Ba0.1Fe0.9Ti0.1O₃ perovskite compound

Abstract

This work focuses on the structural, electrical and magnetic properties of Bi 0:8 Tb 0:1 Ba 0:1 Fe 0:9 Ti 0:1 O 3 ceramics, fabricated by solid state reaction procedure. XRD forms of the samples at RT exhibited perovskite phase through the hexagonal structure at room temperature. Dielectric studies of the materials with frequency at different temperatures (25-400 C) exhibit two dielectric anomalies, first at 175 C (ferroelectric-ferroelectric transition) and second at around 320 C (ferroelectric-paraelectric transition). The Curie temperature moved towards the low side temperature with the increase in frequency. The less value of activation energy got for these samples could be attributed to the influence of electronic contribution to the conductivity. A significant change in the magnetic studies was observed for Bi 0:8 Tb 0:1 Ba 0:1 Fe 0:9 Ti 0:1 O 3 ceramic. The impedance analysis confirms the non-Debye type nature of the ceramic and relaxation frequency moved to a higher temperature. The Nyquist plot and conductivity studies showed the NTCR behavior of samples. The highest magnetization field was found at temperature À268.15 C.

Structural modification and evaluation of Dielectric, Magnetic and Ferroelectric Properties o f Nd- modified BiFeO3– PbTiO3 Multiferroic Ceramics

“…These observed anomalies in the dielectric constant can be correlated to AFM Neel temperature (T N ) and phase transitions of BiFeO 3 and PbTiO 3 compounds which attributed to multiferroic behavior of prepared samples. For rare earth doped BFO, similar anomalies in the dielectric constant have been reported near Néel temperature [31,32].The dielectric anomaly corresponding to Neel temperature shifts towards higher temperature with increase in Nd +3 doping composition. The shift in Neel temperature (T N ) is correlated to the variation of Fe-O-Fe angle due to the structural modi cation by the replacement of Bi +3 ions by Nd +3 ions according to relation, T N = JZS(1+Cos ), where J is exchange constant, S (= 5/2) is spin of Fe +3…”

Study of Dielectric Relaxation Dynamics and Transport Properties of Nd3+-Substituted Bismuth Ferrite Ceramics for Energy Storage Applications

“…Interestingly, for samples with x = 0.15 and 0.2, a third anomaly can be observed at temperatures ∼700 K and ∼685 K, respectively, along with dielectric anomalies between 400 and 500 K. These dielectric anomalies can correspond to antiferromagnetic Neel temperature (T N ) and phase transitions of Bi 1−x Nd x FeO 3 compounds which also have been reported for rare-earth doped BFO at the vicinity of the Neel temperature. 44,45 As the applied frequency increases, the peak position at a specific temperature (T s ) initially shifts toward the higher temperature and then gradually shifts toward the lower temperature, confirming good ferroelectric properties. 39 Additionally, it was noticed that as the Nd 3+ concentration is increased, the ferroelectric T C value decreases from 700 K for x = 0.15 to 685 K for x = 0.2.…”

Investigation of relaxor and diffuse dielectric phase transitions of Ba1-XBixTi0.8Fe0·2O3 materials

“…These tree peaks are due to different phase transitions of BiFeO 3 and BaTiO 3 [ 52 ]. Based on our previous works [ 39 , 40 ] and in accordance with the literature [ 52 , 53 ], these peaks are corresponding to the phase transition from rhombohedral to orthorhombic phase T R-O at low temperature and to tetragonal ferroelectric phase T O-T at intermediate temperature then to a cubic paraelectric phase T m at high temperature. The evolution of dielectric permittivity and transition temperature of these tree phase transitions at 5 KHz are represented in Fig.…”