One-step synthesis of TiO_2 nanorod arrays on Ti foil for supercapacitor application

摘要

Titanium dioxide (TiO_2) nanorod arrays grown directly on Ti metal foil were prepared by a facile one-step hydrothermal method, in which the Ti foil serves as both substrate and precursor. The nanorods are tetragonal rutile single crystal with growth orientation along the [001] direction. The electrochemical properties of the TiO_2 nanorod arrays were systematically investigated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy using a three-electrode system. As a result, the TiO_2 nanorod arrays exhibit good areal specific capacitance and excellent cyclic stability by retaining more than 98% of the initial specific capacitance after 1000 cycles. In addition, a good flexibility of the Ti foil with TiO_2 nanorod arrays was demonstrated by the stable electrochemical performance under different bending angles, which indicates that TiO_2 nanorod arrays grown on Ti foil could be a promising electrode material for flexible supercapacitor application.