Synthesis, structure, electrical conductivity, and magnetic properties of BaMn_1−xNi _xO₃ nano-perovskite

This study details the effect of the co-substitution of Ni⁴⁺ ions for Mn⁴⁺ ions on the structural, morphological, electrical, and magnetic parameters of BaMn_1−xNi_xO₃ (x = 0.1, 0.3, 0.5, 0.7, and 0.9) synthesized by the co-precipitation route. XRD pattern confirmed the hexagonal (P6₃/mmc (194), z = 2) phase for all samples and an additional significant secondaries phases, such as BaMn₂O₃, Mn₂NiO₃, Mn₃O₄, Mn₂NiO₄, and NiO for all doping levels. The crystallite size is obtained to be 36.8 to 90.2 nm and independent of Ni content; such a trend in SEM images presented the regular hexagonal platelets of sizes ~ 84–390 nm. Also, the ratio of Gs/Cs varies between 2 and 5. EDX revealed the presence of constituent elements with their weight percentages in BaMn_1−xNi_xO₃ products. ρ_XRD and ρ_exp are estimated to be around 5.9370 g/cm³. The porosity, P, decreases by 60% with increasing Ni-90%. The σ_DC increases with increasing temperature impress semiconductor behavior. SPH model is the best fit for the conductivity data. The activation energy is calculated to be (0.21–0.33) eV and increased 3 times with increasing Ni content. The magnetic hysteresis loops demonstrate the paramagnetic (PM) behavior for the tested manganite compound, where BaMn_1−xNi_xO₃ possesses paramagnetic phases and increment of Ni-content affects the magnetic parameters as M_s, remnant M_r, H_c, and magnetic moment n_B. H_c increases to 2%; inversely, M_s decreases to 2%, increasing Ni-90%. The attractive electromagnetic properties suggest that BaMn_1−xNi_xO₃ could be a promising potential material in the fabrication of magnetic devices on an industrial scale.