Hierarchical NiO Superstructures/Foam Ni Electrode Derived from Ni Metal-Organic Framework Flakes on Foam Ni for Glucose Sensing

Abstract

The detection of glucose has been attracting more and more attention. The present work provided a novel glucose sensor based on hierarchical NiO superstructures/foam Ni electrode. In this strategy, the foam Ni was chosen as a substrate to grow Ni metal-organic frameworks (NiMOFs) via “twin metal source” method, and then the hierarchical NiO superstructures/foam Ni electrode was constructed by pyrolyzing the corresponding NiMOFs/foam Ni electrode for the first time. The preparation process was carefully characterized by scanning electron microscopy, thermogravimetric analysis and X–ray powder diffraction. The results showed the NiMOFs on foam Ni electrode with morphology of the flakes. After the NiMOFs/foam Ni electrode was pyrolyzed, the hierarchical NiO superstructures/foam Ni electrode was formed and the hierarchical NiO superstructures uniformly embedded in three-dimensional carbon frameworks to enhance the electrical conductivity of hierarchical NiO superstructures. The electrocatalytic properties of hierarchical NiO superstructures/foam Ni electrode were investigated by cyclic voltammetry, amperometry and chronoamperometry. The novel glucose sensor showed a reasonable linear range of 0.018–1.2mM and detection limit of 6.15μM with a high sensitivity of 395μAmmol−1. Such good result renders it promising candidate for routine testing.