Supercapacitive performance of C-axis preferentially oriented TiO2 nanotube arrays decorated with MoO3 nanoparticles

Abstract

Highly ordered TiO₂ nanotube arrays (TNTAs) have received great attention owing to their high surface area, stability and direct transport pathways. The TNTAs, modified with other materials exhibiting enhanced conductivity and capacitance have been considered to be promising anode materials for supercapacitors. In this work, MoO₃/carbon@different crystallography-oriented TiO₂ nanotube arrays (CTNTAs) were synthesized by an anodizing method and electrochemical deposition. The structure and morphology of the samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). The electrochemical performance was tested by cyclic voltammogram (CV) and galvanostatic charge-discharge (GDC) tests. The results indicated that MoO₃/carbon@(004) preferentially oriented TiO₂ nanotube array electrodes have the advantages of combining p-TNTAs and MoO₃ nanoparticles and exhibit high electrochemical performance and cycling stability. The highest specific capacitance of the MoO₃-p-CTNTA electrode achieved is 194 F g⁻¹ at a current density of 1 A g⁻¹.