Decorating Mg/Fe oxide nanotubes with nitrogen-doped carbon nanotubes

Mg/Fe oxide nanotubes decorated with nitrogen-doped carbon nanotubes (CNx) were fabricated by catalytic chemical vapor deposition of ethylenediamine on the outer surface of oxide nanotubes. Mg/Fe oxide nanotubes were prepared using a 3: 1 molar precursor solution of Mg(NO3)(2) and Fe(NO3)(3) and anodic aluminum oxide as the substrate. The obtained samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer (VSM). The XRD pattern shows that the oxide nanotubes are made up of MgO and Fe2O3. TEM and SEM observations indicate the oxide nanotubes are arrayed roughly parallel to each other, and the outer surface of oxide nanotubes are decorated with CNx. XPS results show the nitrogen-doped level in CNx is about 7.3 at.%. Magnetic measurements with VSM demonstrate the saturated magnetization, remanence and coercivity of oxide nanotubes are obvious improved after being decorated with CNx. (C) 2011 Elsevier B.V. All rights reserved.