Ni/CdS Bifunctional Ti@TiO₂ Core–Shell\nNanowire Electrode for High-Performance Nonenzymatic Glucose Sensing

Abstract

In this work, a Ni/CdS bifunctional\nTi@TiO₂ core–shell\nnanowire electrode with excellent electrochemical sensing property\nwas successfully constructed through a hydrothermal and electrodeposition\nmethod. Field emission scanning electron microscopy (FESEM) and transmission\nelectron microscopy (TEM) were employed to confirm the synthesis and\ncharacterize the morphology of the as-prepared samples. The results\nrevealed that the CdS layer between Ni and TiO₂ plays an\nimportant role in the uniform nucleation and the following growth\nof highly dispersive Ni nanoparticle on the Ti@TiO₂ core–shell\nnanowire surface. The bifunctional nanostructured electrode was applied\nto construct an electrochemical nonenzymatic sensor for the reliable\ndetection of glucose. Under optimized conditions, this nonenzymatic\nglucose sensor displayed a high sensitivity up to 1136.67 μA\nmM^–1 cm^–2, a wider liner range\nof 0.005–12 mM, and a lower detection limit of 0.35 μM\nfor glucose oxidation. The high dispersity of Ni nanoparticles, combined\nwith the anti-poisoning faculty against the intermediate derived from\nthe self-cleaning ability of CdS under the photoexcitation, was considered\nto be responsible for these enhanced electrochemical performances.\nImportantly, favorable reproducibility and long-term performance were\nalso obtained thanks to the robust frameworks. All these results indicate\nthis novel electrode is a promising candidate for nonenzymatic glucose\nsensing.