Copper oxide supported on three-dimensional ammonia-doped porous reduced graphene oxide prepared through electrophoretic deposition for non-enzymatic glucose sensing

The paper reports on the preparation of N-doped porous reduced graphene oxide/copper oxide (ammonia-doped-prGO/CuO) nanocomposite on gold electrodes using electrophoretic deposition (EPD) from an ethanolic suspension of ammonia-doped-prGO and Cu(ClO4)2 by applying a DC voltage. The ammonia-doped-prGO/CuO nanocomposite film thickness is controlled by varying the deposition time. Morphological analysis using scanning electron microscopy (SEM) showed the formation of a 3-dimensional structure with CuO nanoparticles being homogeneously embedded in the graphene layer. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman analysis revealed that the deposited copper was in its oxidized form, mainly CuO. The Au/ammonia-doped-prGO/CuO electrode was successfully applied for non-enzymatic amperometric detection of glucose. Under optimized conditions, the electrode exhibited a sensitivity of 1210 μA mM−1 cm−2 with a detection limit of 0.25 μM (S/N = 3) over a wide concentration range (0.25 μM to 6 mM) at an applied potential of +0.50 V vs. Ag/AgCl. The electrode material displayed good stability, excellent selectivity, and accurate measurement in healthy and diabetic human serum samples.