Nanoparticles-assembled NiO nanosheets templated by graphene oxide film for highly sensitive non-enzymatic glucose sensing

Nanoparticles-assembled NiO nanosheets have been successfully prepared using graphene oxide (GO) film as template, where the Ni2+ ion was firstly adsorbed in GO film, followed by calcination in N2 to form NiO-based materials and calcination in air to remove carbon-based template. The morphology, structure, and electrochemical activities of these NiO nanosheets were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and electrochemical techniques, respectively. It is found that the NiO nanosheets thus obtained could electrochemically catalyze glucose oxidation in 0.1 M NaOH, leading to fabrication of non-enzymatic glucose sensor. The glucose sensor based on NiO nanosheets exhibits detection limit of 0.18 μM, and linear range from 1 μM to 0.4 mM with the sensitivity of 1138 μA mM−2 cm−2. Furthermore, such glucose sensor also shows excellent selectivity for detection of glucose, compared to the commonly interfering species, such as ascorbic acid, dopamine, and uric acid.