Synthesis and characterization of structural, electrical, magnetic and microwave properties of Ba_0.5Sr_0.5Fe₁₂O₁₉-polyaniline nanocomposites

In this article, barium strontium hexaferrite was synthesized using the surfactant-free ultrasonic method. Then Ba_0.5Sr_0.5Fe₁₂O₁₉/polyaniline nanocomposites were made in the form of thick layer, thin film and nanofibers. The bulk layer forges via the in-situ synthesis method, and the thin film is synthesized by electrodeposition in cyclovoltammetry mode. The nanofibers were manufactured using the electrospinning method. The products were investigated via X-ray diffractometer, field emission scanning electron microscope, transmission electron microscope, and vibration sample magnetometer. The band gap, exciton binding energy, and the Urbach energy of Ba_0.5Sr_0.5Fe₁₂O₁₉ nanoparticles were calculated by optical and electrical methods. The reflection loss of nanocomposites at frequencies between 2 and 18 GHz was measured by Vector Network Analyzer. The magnetic properties of nanoparticles were weakened by their presence in the polymer matrix. The DC conductivity of polyaniline decreased by adding ferrite nanoparticles to it and reached from 0.67 S.cm⁻¹ in pure polyaniline to 2.5 × 10^–5 S.cm⁻¹ in composite nanofibers. The highest value of reflection loss (RL_min) − 16.99 dB at the frequency (f_min) of 11.2 GHz was obtained for the thick layer nanocomposite.