Three-dimensional macroporous carbon supported hierarchical ZnO-NiO nanosheets for electrochemical glucose sensing

Hierarchical ZnO-NiO nanosheets arrayed on three-dimensional macroporous carbon derived from kenaf stem (3D-KSCs) were constructed by thermal annealing the Zn-doped Ni-metal-organic frameworks grew on the 3D-KSCs for nonenzymatic glucose sensing. The prepared 3D-KSCs/hierarchical ZnO-NiO nanosheets were carefully characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and N 2 adsorption/desorption isotherms. The results showed that the existence of a small quantity of Zn was very important to control the morphology of hierarchical ZnO-NiO nanosheets . The porous structure of 3D-KSCs/hierarchical ZnO-NiO nanosheets enlarged the effective electrode surface area, and enhanced the electrical conductivity and mass transfer of nanocomposites greatly. The as-synthesized 3D-KSCs/hierarchical ZnO-NiO nanosheets was prepared into integrated electrode for nonenzymatic glucose detection, showing a wide linear range from 13 μM to 4.86 mM, a low detection limit of 4.12 μM, fast response time (<3 s) and good sensitivity (448.6 μA mM −1  cm −2 ). The good performances make the 3D-KSCs/hierarchical ZnO-NiO nanosheets be a promising nanocomposite material for electrochemical sensing of glucose.