A highly sensitive enzyme-free glucose sensor based on Co3O4 nanoflowers and 3D graphene oxide hydrogel fabricated via hydrothermal synthesis

A hybrid structure composed of a 3D network of graphene oxide hydrogels (GOHs) and Co3O4 nanoflowers (NFs) was fabricated by using a one pot hydrothermal process. Scanning electron microscopy and transmission electron microscopy revealed the formation of Co3O4 NFs in the GOH networks, which resulted in an increase in the surface area and in electrocatalytic activity. Cyclic voltammetry (CV) was used to evaluate the glucose sensing ability of the various samples fabricated in this study. The Co3O4 NF/GOH sample exhibited glucose sensitivity as high as 492.8 mu AmM-1 cm(-2), which is 20 times that of pure GOH. This sample also exhibited excellent glucose sensing in real blood samples (horse and rabbit serums) as well as a high selectivity toward common interfering species, such as ascorbic acid (AA), uric acid (UA) and dopamine (DA). (C) 2015 Elsevier B.V. All rights reserved.