Effect of rare earth and transition metal La-Mn substitution on electrical properties of co-precipitated M-type Ba-ferrites nanoparticles

In the current research work Ba_1?xLa_xMn_yFe_12?yO₁₉ hexa-ferrite nanoparticles of different compositions were synthesized using chemical co-precipitation technique. The structural properties were explored using X-ray diffractions (XRD), scanning electron microscopy (SEM) and Fourier transmission infrared spectroscopy (FTIR). XRD indexed pattern confirms the formation of M-type hexagonal phase. The crystallite size of synthesized samples ranges from 13 to 34 ± 2 nm. FTIR peaks observe also confirmed the presence of metal–oxygen bond of the desired product. The position of peak at 467 cm^?1 corresponds to A₂u vibration for octahedral Fe(4+)–O and peak position E_1u corresponds to vibration of Fe(3+)O₄ octahedral bonds. The band v₁ in range (677–559 cm^?1) and v₂ in frequency range (356–419 cm^?1) are associated to A and B sites. Dielectric properties of all compositions were measured with frequency. The dielectric constant, loss and tangent loss decrease from 26 to 9, 25 to 2 and 0.94 to 0.14, respectively with frequency. DC electrical resistivity is increased with dopant concentration increasing from 2.15 × 10⁴ to 1.92 × 10⁵ Ω·cm.