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.