Introducing a novel nanocomposite consisting of TiO2 nanoparticles@copper oxide/reduced graphene oxide for the electrocatalytic sensing of ascorbic acid

Abstract

In the present work, titania nanoparticles (TiO2NPs), copper oxide (CuO), and reduced graphene oxide (rGO) ternary nanocomposite (TiO2NP@CuO-rGO)-modified glassy carbon electrode (GCE) have been used for sensitive detection and determination of ascorbic acid (AA). The modified glassy carbon electrode was characterized over the successive modification steps, by scanning electron microscope (SEM) imaging, FT-IR spectroscopy, XRD, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Electrochemical detection and determinations were made using differential pulse voltammetry (DPV), and the amount of ternary nanocomposite (TiO2NP@CuO-rGO), the effect of pH, and potential scan rate were optimized. The electrochemical properties of the AA at the proposed modified electrode were monitored by performing CV experiments. The DPVs and CVs displayed one oxidation peak during the anodic potential scan. The electrochemical detection and determination by DPV provided a linear concentration range from 10.0 pM to 10.0 μM with a limit of detection (LOD) 3.0 pM. The TiO2NP@CuO-rGO/GCE sensor demonstrated good reproducibility, stability, and repeatability and no interference in the electrochemical detection and determination of AA in the presence of many compounds. The suggested method was satisfactory practical for the detection and determination of AA in human synthetic blood serum samples, with recoveries about 99.2%. Titania nanoparticles@copper oxide–reduced graphene oxide: TiO2NP@CuO-rGO. Applicability of the TiO2NP@CuO-rGO nanocomposite in fabrication of an efficient ascorbic acid (AA) sensor based on the use of a glassy carbon electrode.