Temperature and frequency dependence on electrical properties of polyaniline/Ni_(1−x)Co_xFe₂O₄ nanocomposites

Two nanocomposites of polyaniline (PANI) varying in their percentage composition of Ni_(1−x)Co_xFe₂O₄ nanoparticle (20%, 10% w/w of fine powders) were prepared by in-situ chemical oxidative polymerization method with and without ultrasonic treatment. The spinel ferrite nanoparticles of chemical composition Ni_(1−x)Co_xFe₂O₄ were prepared by auto combustion method. The structure and morphology of PANI and nanocomposites were characterized by X-ray diffraction (XRD) and High resolution transmission electron microscopy (HRTEM). The chemical structure of Ni_(1−x)Co_xFe₂O₄ nanoparticles and its composites were characterized by using Fourier transform infrared (FTIR), UV–visible absorption spectrometer and XRD techniques. Dielectric properties of nanocomposites at different temperature have been performed in the frequency range of 50 Hz to 5 MHz. Dielectric constant, dielectric loss and AC conductivity of PANI/Ni_(1−x)Co_xFe₂O₄ nanocomposites are significantly increasing with increase in ferrite content due to the polaron/bipolaron formation. The optical absorption experiments of PANI/Ni_(1−x)Co_xFe₂O₄ nanocomposite illustrate a direct transition with an energy band gap of Eg around 1.7. - Highlights: • The combustion reaction support to achieve less particle size. • The addition of sonic bath affects the properties. • Nature of the ferrites was affected with different composition of PANI