Fabrication of reduced graphene oxide/TiO2 nanorod/reduced graphene oxide hybrid nanostructures as electrode materials for supercapacitor applications

Abstract

Two-dimensional (2D) reduced graphene oxide/titanium dioxide nanorod array/reduced graphene oxide (rGO/TiO₂ NR/rGO) with a porous hybrid structure was fabricated as an electrode material for use in electrochemical supercapacitors. The structural, morphological, and compositional characteristics of the resulting electrode material were evaluated by using X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), and X-ray photoelectron spectroscopy (XPS). The electrochemical behavior of the as-prepared electrodes was characterized by using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) in 1 M Na₂SO₄ aqueous electrolyte. The maximum specific capacitance of this rGO/TiO₂ NR/rGO electrode was 114.5 F g⁻¹ at a scan rate of 5 mV s⁻¹. The electrode exhibited high cycling stability, retaining over 85% of its initial capacitance after 4000 cycles. These results indicate that rGO/TiO₂/rGO is a promising candidate for the electrode material in supercapacitor applications.