Electrochemical Deposition of Graphene Films for Cr(VI) Fast Detection in Water

In this paper, a simple and highly sensitive sensing interface of graphene film for hexavalent chromium (Cr(VI)) determination has been prepared by controllable electrochemical deposition on the gold electrode surface. The graphene film was obtained by direct electroreduction of graphene oxide (GO) in suspension solution. The investigations on deposition parameters of this controllable preparation, such as potential and deposition time, were carried out by the potentiostatic method to study the effects of them on the graphene film. The fabrication process and electrochemical properties of graphene film were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and electrochemical techniques, respectively. The conditional parameters, including detection potential, the concentration of supporting electrolyte and pH, were optimized for Cr(VI) analysis. Without preconcentration, chronoamperometry method was used for Cr(VI) fast detection. Under the optimized conditions, the graphene film modified electrode provided a fast detection process, a wide linear range from 5 μg/L to 2000 μg/L, and a low detection limit of 0.5 μg/L (S/N ≥ 3). Also, the developed graphene film showed a good stability and anti-interference for Cr(VI) determination. The reported work holds promise for practical application due to its simple, fast, environment-friendly and economical natures.