Fabrication of Novel CuO Films with Nanoparticles-Aggregated Sphere-Like Clusters on ITO and Their Nonenzymatic Glucose Sensing Applications

Abstract

In this work, novel nanoparticles-aggregated CuO sphere-like clusters were successfully synthesized on indium tin oxide (ITO) glass through a facile two-step procedure consisting of the fabrication of Cu2O films directly grown on ITO surface by electrodeposition, and subsequent calcinations of Cu2O films leading to the formation of CuO films. The morphology and structure of as-synthesized samples were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was found that the size of nanoparticles constituting sphere-like clusters structure obtained at 200[Formula: see text]C is much smaller than that of obtained at other temperature, which can provide large surface area for catalytic reaction. The CuO/ITO electrode was applied to detect glucose by cyclic voltammetry (CV) and amperometric detection ([Formula: see text]). It was found that the obtained CuO films modified ITO electrode exhibited a much higher electrocatalytic activity for the oxidation of glucose in an alkaline medium through heat treatment of 200[Formula: see text]C. A favorable performance with a high sensitivity of 1841.5544[Formula: see text][Formula: see text]A mM[Formula: see text] cm[Formula: see text] to glucose ranging from 1.0[Formula: see text][Formula: see text][Formula: see text]10[Formula: see text][Formula: see text]M to 5.0[Formula: see text][Formula: see text][Formula: see text]10[Formula: see text][Formula: see text]M, a low operating potential of 0.35 Vversus Ag/AgCl and a fast amperometric response (within 3[Formula: see text]s) were achieved on such CuO/ITO electrode. It also showed outstanding long-term stability and good reproducibility. Notably, poisoning by chloride ions and interference from ascorbic acid, uric acid and acetaminophen were negligible. Therefore, the nanoparticles-aggregated CuO sphere-like clusters would be a promising candidate electrode material for the development of nonenzymatic glucose sensors.