Journal of Electroanalytical Chemistry, Vol.776, 59-65, 2016
Graphene oxide-Cu(II) composite electrode for non-enzymatic determination of hydrogen peroxide
We report a novel graphene oxide-Cu (II) (GO-Cu2+) composite electrode for electrochemical determination of hydrogen peroxide (H2O2) in neutral solution (pH = 7.4). Oxygen functional groups such as carboxylic acid, hydroxyl and epoxy present on GO are utilized for the formation of composite with Cu2+ ions. The GO-Cu2+ composite was modified on the surface of glassy carbon (GC) electrode and characterized by cyclic voltammetry (CV). The surface morphology of the GO and GO-Cu2+ composite materials was observed by scanning electron microscopy (SEM) and elemental analysis was performed using EDS. The prepared electrode showed a good electrocatalytic performance for reduction of H2O2 and mechanistic pathway has been discussed. Amperometric determination for H2O2 was carried out at a applied potential of -0.25 V vs Ag/AgCl and the result showed a linear response range of 5 mu M to 85 mu M (correlation coefficient = 0.999) with a detection limit of 0.5 mu M (S/N = 3). The sensitivity of the electrode was found to be 0.072 mu A mu M-1 and the electrode selectively detected H2O2 in the presence of other potential interferences such as oxygen, glucose, ascorbic acid (AA), dopamine (DA) and uric acid (UA). (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Graphene oxide-Cu (II) composite;Non-enzymatic sensor;Amperometric method;Hydrogen peroxide