Structural, magnetic, and dielectric properties of graphene oxide/ZnxFe1-xFe2O4 composites

Graphene oxide (GO)/ZnxFe1-xFe2O4 (ZFO) (x = 0.1, 0.3, 0.5, and 0.7) composites were synthesized using a facile two-step synthesis process. GO bulk powder was synthesized by the modified Hummer's method and the ZFO nanoparticles (NPs) (particle size 3-12 nm) by chemical co-precipitation method. Structural analysis of GOZFO composites confirms the coexistence of both phases without any additional impurity phase. The saturation magnetization was found to increase with increasing particle size of ZFO in composite samples. Semiconducting nature of the resistance was found to increase with decreasing particle size of ZFO due to enhanced scattering. The dielectric properties of the composite system were also improved by the addition of ZFO NPs and the maximum enhancement was observed in the composite having ultrafine ZFO NPs. These results indicate that GOZFO composites can be seen as the potential candidates for magnetic and capacitive applications. (C) 2015 AIP Publishing LLC.