Influences of annealing temperature on structural characterization and magnetic properties of Mn-doped BaTiO3 ceramics

Abstract

Polycrystalline samples of BaTiO3 doped with 2.0 at. % Mn were prepared by solid-state reaction at various temperatures (Tan) ranging from 500 to 1350 °C, used high-pure powders of BaCO3, TiO2, and MnCO3 as precursors. Experimental results obtained from x-ray diffraction patterns and Raman scattering spectra reveal that tetragonal Mn-doped BaTiO3 starts constituting as Tan ≈ 500 °C. The Tan increase leads to the development of this phase. Interestingly, there is the tetragonal-hexagonal transformation in the crystal structure of BaTiO3 as Tan ≈ 1100 °C. Such the variations influence directly magnetic properties of the samples. Besides paramagnetic contributions of Mn2+ centers traced to electron spin resonance, the room-temperature ferromagnetism found in the samples is assigned to exchange interactions taking place between Mn3+ and Mn4+ ions located in tetragonal BaTiO3 crystals.

Electrical and magnetic phase transition studies of Fe and Mn co-doped BaTiO 3

“…The red shifting of the peak may be due to the larger atomic mass of Mn than Ti [35]. Another consequence of Mn doping is the formation of three new vibrational bands observed at 539 cm -1 , 603 cm -1 and 676 cm -1 of which the later two is reported earlier for the Mn doped BTO [11,35]. …”

“…The Fe doping in A-site of BaTiO 3 ceramics hassled to a relaxor ferroelectric behaviour reported by Maikhuri et al [9]. A rich profusion of reports is available in the case of Mn doping in B-site with reasonably good values of magnetisation [10,11]. The effect of concurrent doping with combination of Ca (A-site)-Fe (B-site) and Zn (A-site)-Mn (B-site) in BaTiO 3 is investigated by Chakraborty and Ray [12] and Das et al [13] respectively.…”

Phase formation, microstructure, electrical and magnetic properties of Mn substituted barium titanate

“…From the above result we demonstrated that all these three oxidation states of Mn are present in our BaTi 1-x Mn x O 3 samples. Usually Mn 2+ with greatest r ion is found in BaTi 1-x Mn x O 3 which is annealed in the reducing atmosphere conditions[4,25]. The electron configuration d 4 of Mn 3+…”

Effect of Cobalt substitution on the structural, electrical and magnetic properties of BaTiO<inf>3</inf> ceramics

“…BaTiO 3 (BTO) is known to have a perovskite structure where 3d transition metal can easily substitute for titanium atom due to their similarity in size and valence [5]. BaTiO 3 has excellent ferroelectric and dielectric properties such as high dielectric constant and low dielectric loss, chemical stability and low toxicity [6][7]. Basically, multiferroic materials can be fabricated by means of two routes.…”

“…Basically, multiferroic materials can be fabricated by means of two routes. One route is the composite combining a ferroelectric material with a ferromagnetic material while the other is doping of magnetic impurities into a ferroelectric host material [1][2][3][5][6][7]. In this work, we present a systematic study on BaTiO 3 substituted with different concentration of Co at the Ti site.…”