Synthesis and electrochemical properties of CeO2 nanoparticle modified TiO2 nanotube arrays

Abstract: In this paper, a cerium dioxide (CeO2) modified titanium dioxide (TiO2) nanotube array film was fabricated by electrodeposition of CeO2 nanoparticles onto an anodized TiO2 nanotube array. The structural investigation by X-ray diffraction, scanning electron microscopy and transmission electron microscopy indicated that the CeO2 nanoparticles grew uniformly on the walls of the TiO2 nanotubes. The composite was composed of cubic-phase CeO2 crystallites and anatase-phase TiO2 after annealing at 450°C. The cyclic voltammetry and chronoamperometric charge/discharge measurement results indicated that the CeO2 modification obviously increased the charge storage capacity of the TiO2 nanotubes. The charge transfer process at the surface, that is, the pseudocapacitance, was the dominate mechanism of the charge storage in CeO2-modified TiO2 nanotubes. The greater number of surface active sites resulting from uniform application of the CeO2 nanoparticles to the well-aligned TiO2 nanotubes contributed to the enhancement of the charge storage density. [Copyright &y& Elsevier]