Properties of carbon nanotube/alumina nanocomposites synthesized by various magnetic catalysts

We report on the synthesis of carbon nanotube/alumina nanocomposites (CNTs- Al₂O₃) using chemical vapor deposition process. Magnetic nanoparticles including cobalt, iron, or nickel served as the catalyst for the graphitization of the carbon precursor. Incorporation of CNTs possessing remarkable mechanical, thermal, electrical, and magnetic properties onto the alumina matrix enables the development of nanocomposites with various functionalities. The structures and morphologies of the as-prepared samples were characterized by transmission electron microscope, scanning electronic microscope, X-ray diffractometer, thermogravimetric analyzer, and Mössbauer spectroscopy. The experimental results show that these as-synthesized composites contain CNTs distributed homogenously within the alumina matrix. Magnetic properties of the samples were measured using vibrating sample magnetization at room temperature and under cryogenic conditions. Such characterization is necessary for the wide-spread application of magnetic nanocomposites in different fields.