Effect of SmFeO3 content on structure and multiferroic properties of mSmFeO3–Bi4Ti3O12 thin films

Abstract

mSmFeO3–Bi4Ti3O12 (m = 0.5, 1.0, 1.5, 2.0) thin films were prepared on silicon wafer by sol–gel progress. Their structure, leakage current density, ferroelectricity, magnetism, and dielectric property were investigated. All the samples have a single-phase Aurivillius structure. The interplanar spacing and volume of the unit cell decrease with the increase of SmFeO3 content. Moreover, the multiferroic properties have been significantly improved, with 2Prmax ~ 62 μC/cm2 (m = 0.5) and Msmax ~ 5.8 emu/cm3 (m = 2) at room-temperature. The samples with m = 0.5, 1, 1.5 exhibit Ohmic mechanism-dominated conductive behavior, however, for m = 2 sample, the space-charge-limited current mechanism becomes dominant. The dielectric constant er of the thin films at 1 MHz for m = 0.5, 1.0, 1.5 and 2.0 are 498, 485, 272, and 217 respectively.