Vertically aligned TiO2 nanorod arrays for electrochemical supercapacitor

Vertically aligned TiO2 nanorod (NR) arrays have been prepared on the fluorine doped tin oxide (FTO) substrates using a facile hydrothermal method and the nanostructures were employed as the electrode materials for supercapacitors. The XRD and FT-IR spectra confirmed that the TiO2 nanorods were crystallized in the tetragonal rutile phase. FE-SEM images showed the well aligned TiO2 NRs are uniform and densely covered on the surface of the FTO substrate. The electrochemical performance of the as prepared TiO2 NR electrode was evaluated using the cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge (GCD) measurements in 1 M Na2SO4 electrolyte solution. The results showed that the TiO2 NR electrode exhibited a maximum specific capacitance of 85 μF cm−2 at a scan rate of 5 mV s−1 and good charge/discharge property with 80% stability even after 1000 cycles.