Phase transitions in multiferroic Bi_1−xEu_xFeO₃ synthesized by sol-gel method

Abstract

Bi1-xEuxFeO3 micropowders 0≤x≤0.20 were synthesized by sol-gel method. X-ray diffraction shows that the crystal structure of the samples changes from rhombohedral to cubic symmetry at x=0.20. Dielectric properties and loss factor were investigated as a function of temperature. Neel temperature T_N of the compounds was measured by differential scanning calorimetry and found to decrease from 668 K to 646 K for 0≤x≤0.15 and bounce to 667 K for x=0.20. The Curie temperature TC which corresponds to the transition from ferroelectric to paraelectric phases was checked out using differential thermal analysis (DTA) measurements. The TC value increases from 1130 K to 1135 K for 0≤x≤0.15 while no transition was detected for x=0.20 in accordance with the structural transition from R3c phase to centrosymmetric Pm3m phase.

Novel double structural transition at room temperature in Bi1-xGdxFeO3 system prepared by sol-gel method

“…4, and various thermal anomalies are observed at T H , T F and T N . For all the curves, we note the appearance of a wide valley at T H with a minimum temperature close to 470 K. This feature remains unaffected by Gd substitution, indicating the establishment of the harmonic cycloidal structure, as previously observed in Bi 1-x Eu x FeO 3 [24].…”

Effect of Ho3+ Doping on Structural and Magnetic Properties of Multiferroic YbMnO3

“…Their costeffectiveness and scalability in synthesis procedures added to their attraction to large-scale manufacturing. 8 Therefore, optimizing the performance of currently available multiferroic materials at ambient temperatures continues to be a basic and fascinating problem.…”