Facile growth of Cu2O hollow cubes on reduced graphene oxide with remarkable electrocatalytic performance for non-enzymatic glucose detection

Abstract

In this work, cuprous oxide (Cu₂O) hollow cubes were synthesized on reduced graphene oxide (RGO) nanosheets by a facile one-pot refluxing approach. The as-prepared Cu₂O/RGO nanocomposites were characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. It was revealed that Cu₂O with a well-defined hollow cubic morphology is homogeneously dispersed on the surface of RGO nanosheets. The electrocatalytic properties of Cu₂O/RGO nanocomposites for glucose oxidation were investigated by cyclic voltammetry and chronoamperometry. It was found that the constructed glucose sensor has a wide linear range of 0.01–9.0 mM (R² = 0.996) with a high sensitivity of 813.713 μA cm⁻² mM⁻¹ and a low detection limit of 0.44 μM based on signal/noise = 3. Compared to bare Cu₂O and previously reported Cu₂O-based glucose sensors, the as-prepared Cu₂O/RGO nanocomposite glucose sensor showed remarkably enhanced electrocatalytic activity. In addition, the electrode also exhibited an excellent anti-interference ability. The excellent electrocatalytic performance together with simple and low-cost preparation makes Cu₂O/RGO nanocomposites attractive for glucose sensor application.