Preparation of SiO2 nanowire arrays as anode material with enhanced lithium storage performance.

Abstract

SiO2 nanowire arrays have been prepared by a template-assisted sol gel method and used as a negative electrode material for lithium ion batteries. Amorphous SiO2 was confirmed by X-ray diffraction and Fourier transform infrared spectroscopy. The results of scanning electron microscopy and transmission electron microscopy confirmed that the SiO2 nanowire had a diameter of about 100 nm and a length of about 30 μm. Cyclic voltammetry and constant current charge and discharge tests showed the prepared SiO2 nanowire arrays were electrochemically active at a potential range of 0.05–3.0 V. At a current density of 200 mA g−1, the first discharge specific capacity was as high as 2252.6 mA h g−1 with a coulombic efficiency of 60.7%. Even after about 400 cycles, it still maintained 97.5% of the initial specific capacity. Moreover, a high specific capacity of 315 mA h g−1 was exhibited when the current density was increased to 2500 mA g−1. SiO2 nanowire array electrodes with high reversible capacity and good cycle performance provide potential anode materials for future lithium-ion batteries.