Preparation and magnetic properties of nano-Ni coated cenosphere composites

Ni coated cenosphere composites are successfully fabricated by heterogeneous precipitation method using metal salts, ammonium hydro-carbonate and cenospheres as the raw materials. The cenosphere particles are characterized by scanning electron microscope (SEM)/energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) during and after the coating process. All results show that relatively uniform, smooth and compact Ni layer has been successfully coated onto cenospheres under the given conditions, furthermore, the nanometer Ni crystallite has a face-centered cubic structure. Magnetic property of Ni coated cenosphere composites can be adjusted by controlling the synthesis conditions and content of magnetic metal. The low density Ni coated cenosphere composites may be utilized for electromagnetic wave shielding and microwave absorbing materials. (C) 2010 Elsevier B.V. All rights reserved.