Assessing the electrochemical performance of hierarchical nanostructured CuO@TiO2 as an efficient bi-functional electrocatalyst

Abstract

Fabrication and attractive performance of CuO nanoparticles coated onto TiO2 substrate (CuO@TiO2) as electrocatalysts for glucose and methanol electrooxidation are detailed in this article. These bi-functional electrocatalysts were prepared by impregnating (5–25 wt%) CuO nanoparticles onto nanosized TiO2 substrate and were characterized for morphology and composition. Cyclic voltammetry and electrochemical impedance spectroscopy provided a detailed account of their electrochemical capacity. All samples in CuO@TiO2 series were tested for probable electrocatalysis; however, 5CuO@TiO2 possessed significantly improved electrocatalytic activity for methanol and glucose electrooxidation. This can be attributed to the better conductivity of the electrocatalyst showing that electrocatalytic activity is limited by the amount of CuO loading on CuO@TiO2 electrocatalyst. The involvement of the Cu (II) to Cu (III) reversible redox couple was evident in the electrocatalytic oxidation. The sensitivity of 7.15 μA mM−1 cm−2 and a detection limit of 235.0 μM for glucose at a signal to noise ratio of 3 were obtained using 5CuO@ TiO2-modified glassy carbon electrode.