Assembly of Ni(OH)2 nanoplates on reduced graphene oxide: a two dimensional nanocomposite for enzyme-free glucose sensing

Abstract

Ni(OH)₂ nanoplates were successfully synthesized and in situ assembled on reduced graphene oxide (RGO) nanosheets by a simple one-pot method. This RGO-Ni(OH)₂ nanocomposite was characterized by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD), Raman and X-ray photoelectron spectroscopy (XPS). TEM images showed that the composite was round and that leaf-shaped nanoplates with a diameter of about 150 nm assembled on the RGO nanosheets. EDX, XRD, Raman and XPS characterization proved that the constituent parts of the composite were Ni(OH)₂ and RGO. Moreover, the amount of Ni(OH)₂ assembled on the RGO could be adjusted simply by changing the volume of NiCl₂ added to the reactant mixture. For the strong catalytic ability of the high-valent oxydroxide species (NiOOH) formed in alkaline media, the RGO-Ni(OH)₂ nanocomposite was used as the matrix for the non-enzymatic detection of glucose. A low detection limit of 0.6 μM with a wide linear range from 2 μM to 3.1 mM (R = 0.9987) could be obtained. The operating simplicity and low expense of fabrication make this Ni(OH)₂-based electrode attractive in sensor construction.