Impact of magnetic spinel ferrite content on the structure, morphology, optical, and magneto-dielectric properties of BaTiO3 materials

Abstract

Abstract In this study, the influence of magnetic content of NiFe1.93Dy0.07O4 spinel ferrite on the structural, morphological, optical, and magneto-dielectric properties of BaTiO3 materials was investigated. NiFe1.93Dy0.07O4 magnetic nanoparticles and BaTiO3 dielectric materials were firstly synthesized using the hydrothermal method and sol–gel auto-combustion route, respectively. Then, different contents of the magnetic nanoparticles were added to BaTiO3 to form a series of BaTiO3/(NiFe1.93Dy0.07O4) x samples (abbreviated as BTO/(NDFO) x ) with x = 0, 2, 5, 10, 20, and 100 %. The analysis of the structure via X-ray diffraction (XRD) technique revealed a transformation from a tetragonal structure for the pristine BTO sample to a cubic structure upon the inclusion of magnetic nanoparticles. The morphological observations and chemical composition analyses via scanning electron microscope (SEM) coupled with EDX system showed the successful formulation of biphasic products. The optical properties were investigated, and it was found that the inclusion of the magnetic phase diminishes the bandgap energy (E g ) of final BTO/(NDFO) x samples. Furthermore, vibrating sample magnetometer (VSM) was used to investigate the magnetization properties. The values of saturation magnetization (M S ) and remanent (M r ) magnetization are rising with the increase of magnetic phase content. However, the coercivity (H c ) does not show a regular variation with the increase of NDFO content. The dielectric properties were also investigated for different BaTiO3/(NiFe1.93Dy0.07O4) x samples. The obtained results showed that the real permittivity (ε′) and dielectric tangent loss (tan δ) increased with increasing temperature. Remarkably, the addition of magnetic content provokes a reduction in tan δ values compared to the pristine BTO sample. The lowest values of tan δ and highest frequency stability were noticed in the sample added with 10 % of magnetic phase. The impedance and modulus were also determined and discussed.