Structural, magnetic and dielectric properties of ultrafine nickel substituted cobalt ferrite− reduced graphene oxide nanocomposites

Abstract

Nickel substituted cobalt ferrite − reduced graphene oxide (NCF-RGO) composite was synthesized using a facile one-pot chemical co-precipitation method. The addition of graphene oxide (GO) leads to the dimensional decrease of NCF nanoparticles (< 10 nm) in the composite, which controls the magnetic and dielectric properties. Nickel with lower ionic radius, compared to cobalt and its substitution in the composite along with the incorporation of GO results in the transition of ferromagnetic to superparamagnetic ordering. A large magnetisation of 51.63 emu/g and a high dielectric constant of 3.92 x 10 6 (at 100 Hz) were also developed from the composite. The conjugated mechanism of magnetic combined electrical property, with a high charge–storing capability and tuneable magnetization, enables its potential use in magnetic flipping or switching devices and data storing systems.