Structural, electrical, and weak ferromagnetic-to-antiferromagnetic nature of Ni and La co-doped BaTiO₃ by sol–gel combustion route

We report on structural, electrical, and weak ferromagnetic-to-antiferromagnetic possessions of Ba_(1−x)La_xNi_0.01Ti_0.99O₃ (BLNT) samples with x = 0.00, 0.25, 0.50, and 0.75%. The X-ray diffraction (XRD) and Raman spectra show that the sol–gel combustion route synthesized samples are successfully incorporated with La³⁺ ions into BaNi_0.01Ti_0.99O₃ (BNT) lattice. The EPR signals at g = 1.967 and g = 2.003 are attributed to the V_(Ba) and V_(Ti) defects, respectively. For x = 0.75%, V_(Ba) signal disappears due to the subtle charge-compensation mechanism present in the BLNT sample. The BNT ceramics exhibit a weak ferromagnetic nature; upon La ion doping, the weak ferromagnetic (WFM) tends to exhibit strong antiferromagnetic (AFM) nature in BLNT. This magnetic phase transition can be described in the stipulation of the change in the oxidation state. Escalating in the dielectric constant and ac conductivity was due to the higher doping concentration of La³⁺ ion in BNT ceramics. BLNT clearly shows that as La³⁺ ion-doping concentration increases, the diameter of the impedance semicircle decreases due to the increased conducting nature of the samples. The ferroelectric property was deliberately investigated by a P–E hysteresis loop and its saturation polarization was found to decrease with increasing concentrations of La³⁺ ion doping, and the observed results are discussed. [Figure not available: see fulltext.].