CoNiO nanowire arrays as a high-performance anode material for lithium-ion batteries

CoNiO nanowire arrays loaded on TiO2 nanotubes (CoNiO/TiO2NTs) are synthesized by a hydrothermal method and used firstly as an anode material for lithium-ion batteries. The morphology, structure and composition of the composite are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The EDS patterns display the atomic ratio of Co to Ni is 0.41:0.59 with accuracy of more than 99%. SEM images show that the diameters of these nanowires range from 10 to 40 nm and the average length approximately 1 mu m. Electrochemical characterizations are performed in a three-electrode system to determine the capacity, cyclic stability and to investigate the reaction mechanism. As an anode material for lithium-ion batteries, the CoNiO/TiO2NTs nanocomposite delivers a high areal capacity of 362 mu Ah cm(-2) (1097 mAh g(-1), 0.33 mg cm(-2)) after 40 discharge/charge cycles at a current density of 0.2 mA cm(-2) (about 606 mA g(-1)). EIS results show that addition of Ni to the CoO could increase the conductivity of the composite significantly and improve the kinetic behavior during discharge-charge process. The present finding provides a kind of nanostructure fabrication that might be applied in supercapacitor and solar cells, etc. (C) 2013 Elsevier B.V. All rights reserved.