Surface magnetic interactions between Bi_(0.85)La_(0.15)FeO_3 and BaFe_(12)O_(19) nanomaterials in (1-x)Bi_(0.85)La_(0.15)FeO_3-(x)BaFe_(12)O_(19) nanocomposites

摘要

Two different sets of multiferroic nanocomposites i.e., Bi_(0.85)La_(0.15)FeO_3-(x)BaFe_(12)O_(19) with ⅹ = 0.00, 0.05, 0.10, 0.20, 0.30, 0.40, 0.50 and 1.00 have been synthesized by the solid-state reaction method and high energy planetary ball mill techniques. The peaks in the XRD patterns can be indexed to R3c crystal symmetry of Bi_(0.85)La_(0.15)FeO_3 and P63/mmc crystal symmetry of BaFe_(12)O_(19). It suggests the absence of any major chemical reaction between the two phases. Moreover, it is assumed thatBi_(0.85)La_(0.15)FeO_3 and BaFe_(12)O_(19) crystal symmetries are present in the composite independently. Magnetic properties have been improved significantly due to the incorporation of BaFe_(12)O_(19) in the composites. Vegard's law suggests that the experimentally observed magnetizations are higher than that of theoretically calculated value. The difference between the theoretical and experimental magnetization as well as the anomaly in the magnetic hysteresis have been explained by considering the magnetic interaction correlation length between Bi_(0.85)La_(0.15)FeO_3 and BaFe_(12)O_(19) magnetic phases. The hysteresis loop width (ΔH) versus M plots has been introduced to understand the magnetic interaction (exchange bias) between Bi_(0.85)La_(0.15)FeO_3 and BaFe_(12)O_(19). Magnetocrystalline anisotropy increases with the increase in the percentage of BaFe_(12)O_(19) in the composite.