Porous Cu-NiO modified glass carbon electrode enhanced nonenzymatic glucose electrochemical sensors.

Porous Cu-NiO nanocomposites were successfully prepared by calcination of the Cu-Ni(OH)(2) precursor at 400 °C for 2 h. During the process of calcination, Ar was used to deaerate O(2). The structure and morphology of Cu-NiO were characterized by X-ray diffraction spectrum (XRD), energy dispersive X-ray analyses (EDX), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Using porous Cu-NiO nanocomposites, a simple non-enzymatic amperometric sensor has been fabricated (Cu-NiO/GCE) and evaluated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and typical amperometric method. When applied to detect glucose by the amperometric method, Cu-NiO/GCE produced an ultrahigh sensitivity of 171.8 μA mM(-1), with a low detection limit of 0.5 μM (S/N = 3). What's more, interference from common co-existing species, such as UA, AA, and fructose can be avoided at the sensor. Results in this study imply that porous Cu-NiO nanocomposites are promising nanomaterials for the enzyme-free determination of glucose.