Hydrothermally synthesized NiFe 2 O 4 /rGO composites: structure, morphology and electrical conductivity

The effect of thermal treatment on the structural arrangement and pore size distribution in NiFe 2 O 4 /reduced graphene oxide composite materials has been studied using X-ray diffraction, Mössbauer spectroscopy, and nitrogen adsorption/desorption technique. Composite materials have been successfully synthesized by the joint hydrothermal method using graphene oxide colloidal solution obtained by the modified Tour method. The electrical properties of the composite materials, as well as the pure component, have been studied in the frequency range from 0.1 Hz to 1 MHz, in the temperature range from 25 to 175 °C using impedance spectroscopy. A synergetic increase in the electrical conductivity of composite materials compared to pure components has been observed. The activation energies of interparticle hopping of charge carriers have been calculated using Arrhenius-type conductivity plots.