Magnetic properties of NiFe2O4/carbon nanofibers from Venezuelan petcoke

NiFe2O4/carbon nanofibers (NiFe2O4/CNFs) have been successfully synthesized by hydrotermal method using Venezuelan petroleum coke (petcoke) as carbon source and NiFe2O4 as catalyst. The morphology, structural and magnetic properties of nanocomposite products were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), vibrating sample magnetometry (VSM) and electron paramagnetic resonance (EPR). XRD analysis revealed a cubic spinet structure and ferrite phase with high crystallinity. HR-TEM reveals the presence of CNFs with diameters of 4 +/- 2 nm. At room temperature, NiFe2O4/CNFs show superpararnagnefic behavior with a maximum magnetization of 15.35 emu/g, Our findings indicate that Venezuelan petroleum coke is suitable industrial carbon source for the growth of magnetic CNFs. (C) 2014 Elsevier B.V All rights reserved.