Hydrothermal synthesis of glucose derived carbon surface on cupric oxide (C@CuO) nanocomposite for effective electro-oxidation of catechol

In this work, we prepared carbon surface on cupric oxide (C@CuO) utilizing facile hydrothermal with glucose as a carbon precursor and applied it in different annealing treatments (300, 400, and 500 °C). As-prepared materials were characterized by various physicochemical techniques such as FE-SEM, EDX, elemental mapping analysis, XRD, Raman, and EIS spectroscopy. The composite C@CuO annealed at 400 °C (C@CuO-2) shows a considerable amount of carbon surface on metal oxide (CuO) with a well-defined structure, high crystallinity, and low charge transfer resistance. The as-prepared composites were exploited to reduce the charge transfer resistance and enhance the electrocatalytic properties. Due to the promising properties of C@CuO-2, it is utilized as an active electrode modifier (C@CuO-2/GCE) for the electrochemical sensing of Catechol (CC). The electrochemical experiments were performed using cyclic voltammetry (CV) and amperometric (i-t) techniques. This C@CuO-2 composite shows an excellent activity towards the oxidation of CC compared to C@CuO-1 & 3 respectively. In addition, the C@CuO-2 modified GCE exhibits a substantial linear range (0.001 to 15.75 mM), sensitivity (259.19 µA mM⁻¹ cm⁻²), and limit of detection (0.023 µM) respectively. Moreover, the C@CuO-2 composite also shows the perspective applications in real samples analysis.