A highly sensitive non-enzymatic glucose sensor based on CuS nanosheets modified Cu2O/CuO nanowire arrays

CuS nanosheets modified Cu2O/CuO nanowire arrays (NWAs) were successfully fabricated on Cu foil by in-situ growth and successive ionic layer adsorption and reaction (SILAR) methods without binders. The three-dimensional Cu2O/CuO NWAs not only showed strong binding force with current collector but also provided abundant surface area to support CuS nanosheets. Different morphologies of CuS were obtained by varying the Cu(NO3)(2) and Na2S concentrations and the SILAR cycle. When these step-wise prepared products were employed for non-enzymatic glucose sensing, the amperometric response of the optimized CuS/Cu2O/CuO/Cu electrode was approximately twice of that of Cu2O/CuO/Cu electrode. The result is attributed to the modification of CuS nanosheets with suitable amount which increases the active surface area of the electrode. This designed electrode presents an ultrahigh sensitivity of 4262 mu A mM(-1) cm(-2) in the range from 0.002 to 4.096 mM, as well as the excellent selectivity, reproducibility and stability. Moreover, due to the facile preparation and the low cost of Cu based sensors, the CuS/Cu2O/CuO/Cu electrode will be one kind of promising materials for constructing practical nonenzymatic glucose sensors. (C) 2020 Elsevier Ltd. All rights reserved.