Sandwich nanoporous framework decorated with vertical CuO nanowire arrays for electrochemical glucose sensing

Abstract

Increasing demands for electrochemical glucose sensors with high overall performance have recently attracted intensive attention. Herein, we report a novel sandwich-like nanoarchitecture composed of uniform CuO nanowire array layers grown on the nanoporous Cu2O film, which was synthesized via annealing the nanoporous copper thin film obtained by dealloying Cu-based metallic glass precursors. The glucose sensor based on the newly developed CuO/Cu2O nanocomposite exhibits prominent overall electrocatalytic performance towards the oxidation of glucose with a wide linear dynamic detection range from 0.1 to 6 mM, high sensitivity up to 1.95 mA/cm2·mM, fast response time of less than 1.5 s, low detection limit of 1 μM (S/N = 3) as well as excellent selectivity. The enhanced electrocatalytic property of the nanocomposite is attributed to the high surface area originating from the in-situ grown CuO nanowire array structure and synergetic bi-continuous nanoporous Cu2O substrate. This finding not only provides promising candidates for blood glucose sensing, but also opens a new avenue to designing nanostructured catalysts for engineering applications in general.