One-step formation of a hybrid material of graphene and porous Ni with highly active Ni(OH)2 used for glucose detection

Abstract

A hybrid material of graphene and porous Ni with highly active Ni(OH)2 was formed through a one-step electrochemical exfoliation assisted method. The porous Ni with a pore size of 2–10 micrometers obtained by a hydrogen bubble template method was used as the cathode while the graphite foil was used as the anode with only (NH4)2SO4 as the electrolyte. Both the high surface areas of porous Ni and the oxygen radicals in graphene favored the formation of the Ni(OH)2. It is confirmed by energy dispersion spectrum, transmission electron microscope, Raman spectroscopy, x-ray diffraction and x-ray photoelectron spectroscopy analysis. Both the active area and the glucose sensing property of the as-prepared hybrid material were estimated by electrochemical methods of cyclic voltammetry with current-voltage (C-V) curve, chronoamperometry with current-time (I-t) curve and electrochemical impedance spectroscopy analysis, respectively. It shows an extraordinary active area as well as a low charge transfer resistance and absorption resistance. As a result, a high sensitivity of 6504 μA/mM−1 cm−2 within a linear range of 4 μM–1.0 mM was obtained for glucose detection.