Electrochimica Acta, Vol.156, 274-282, 2015
Composites of rutile TiO2 nanorods loaded on graphene oxide nanosheet with enhanced electrochemical performance
TiO2 nanorod/graphene oxide (TiO2 nanorod/GO) composites with different TiO2/GO weight ratios were successfully prepared by self-assembly of GO and ready-made TiO2 nanorods under room temperature conditions. TiO2 nanorods were synthesized via the hydrothermal method, and GO was obtained via a modified Hummers method. X-ray diffraction, atomic force microscopy, and high-resolution transmission electron microscopy indicated that rutile TiO2 nanorods were loaded on the GO nanosheet without obvious aggregation. The electrochemical performance of the TiO2 nanorod/GO composites was confirmed by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy in 1 mol L-1 Na2SO4 aqueous electrolyte. The ratio of TiO2 nanorods to GO in composite materials has significant influence on electrochemical performance of composite electrodes. TiO2 nanorod/GO composites with 4.00 wt.% GO have excellent electrochemical performance. The maximum specific capacitance of this composite electrode was 100 F g(-1) at 5 mVs(-1) scan rate. The TiO2 nanorod/GO composites also exhibited good electrochemical stability with a capacitance degradation of less than 20% over 3000 cycles. The electrochemical performance of the as-prepared nanocomposites could be enhanced by increasing chemical interactions between TiO2 and GO. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords:TiO2 nanorod/graphene oxide;composite materials;modified Hummers method;self-assembly;electrochemical performance