Effect of equiproprotional substitution of Zn and Mn in BaTiO3 ceramic—An index to multiferroic applications

Abstract

This paper reports that ferromagnetism (FM) can be induced in ferroelectric barium titanate (BaTiO 3 ) ceramic with selection of appropriate substituents like Zn and Mn. High density polycrystalline samples of Zn and Mn substituted BaTiO 3 (Ba 1x Zn x Ti 1x Mn x O 3 , x=0, 0.02, 0.04, 0.06, 0.08 and 0.1) were prepared using slow step solid state sintering technique to study the effect of equiproprotional substituents on structural, ferroelectric and magnetic properties of BaTiO 3 (BTO). High precision electrical and magnetic measurements were carried out along with XRD, XPS, and SEM to understand and co-relate magnetic and ferroelectric hysteresis loop observed at room temperature with different values of 'x'. It is seen that ferroelectric hysteresis loop (P~E) is deteriorated (became lossy type) with the increase of Zn and Mn concentration. However, at x=0.1, the material showed the signature of room temperature ferromagnetism, which is an index for BTO to became a promising material for multiferroic applications. M~H loops observed in Zn and Mn substituted BTO are expected to be due to the formation of oxygen vacancies and exchange interaction induced magnetism.

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

“…Multiferroics are the class of materials that exhibit more than one type of ferroic order parameters such as ferroelectricity, ferromagnetism and ferroelasticity [1][2][3][4][5].…”

“…These materials have received tremendous attention in recent years due to their potential application in high speed nonvolatile and holographic memories, microelectromechanical systems, pyroelectric detectors, transducers, sensors etc [2][3][4]6].…”

“…The first and most common approach is to substitute the magnetic ion impurity into the ferroelectric host materials, due to their close resemblance to the host ion in size and valency [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. The second approach is the combination of a ferroelectric material and ferromagnetic material in the form of either bulk or thin films [2][3]18].…”

“…The first and most common approach is to substitute the magnetic ion impurity into the ferroelectric host materials, due to their close resemblance to the host ion in size and valency [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. The second approach is the combination of a ferroelectric material and ferromagnetic material in the form of either bulk or thin films [2][3]18]. It has been found that the properties of BaTiO 3 are sensitive to variation of processing parameters, temperature, crystal structure, particle size, impurities and defect density [2,4,[8][9][10][11][12][13][18][19][20][21][22][23].…”

“…The second approach is the combination of a ferroelectric material and ferromagnetic material in the form of either bulk or thin films [2][3]18]. It has been found that the properties of BaTiO 3 are sensitive to variation of processing parameters, temperature, crystal structure, particle size, impurities and defect density [2,4,[8][9][10][11][12][13][18][19][20][21][22][23].…”