Fabrication of RGO-NiCo2O4 nanorods composite from deep eutectic solvents for nonenzymatic amperometric sensing of glucose.

A novel reduced graphene oxide supported nickel cobaltate nanorods composite (RGO-NiCo2O4) was prepared by a simple ionothermal method in deep eutectic solvents for the first time. Electrochemical results demonstrated that the obtained nanocomposite modified glassy carbon electrode exhibited excellent electrocatalytic performance towards the oxidation of glucose with a wide double-linear range from 1 μM to 25 mM and a low detection limit of 0.35 μM (S/N = 3). NiCo2O4 nanorods with many small interconnected nanoparticles provided many electrocatalytic active sites, while RGO with large surface area offered good electrical conductivity. The synergistic effect between NiCo2O4 nanorods and RGO contributed to the enhanced sensing ability of the hybrid nanostructure. This sensitive glucose sensor can be also used for the practical detection of glucose in human serum.