In this postdoctoral project will be electrochemically studied, characterized and applied electrochemical electrodes based on graphene , tridimensional reticulated vitreous carbon (3D-RVC) or not modified with metal nanoparticles of gold and platinum.The nanoparticles will be previously synthesized (chemically) and surrounded by different protective molecules (surfactants, polyelectrolytes, and others) for their potential application as catalytic material at determination of organic species with pharmaceutical and environmental interest.After the proposed nanoparticle synthesis, it must be deposited in a film form and incorporated on a graphene or 3D-RVC substrate. The electrochemical characteristic of the sensors will be evaluated by electrochemical techniques, namely, cyclic voltammetry, cronoamperometry and electrochemical impedance spectroscopy. With such modifications, the objective is to improve significantly the detection properties of these electrochemical sensors, namely, diminishes of the overpontential work, increase of the current intensity (increase at the analytical signal), increase of sensitivity (increase of the slope of the analytical curve). Hereafter will be employed the use of electrochemical probe that presents a well known behave and extensively discussed at literature, like potassium hexacyaneferrate(III) or hexaammineruthenium(III) in such a way that the comparison/determination of the electroactive area, electronical transference constant and heterogeneous electronical transference constant can be made.For the results obtained by the analyses using graphene modified with metallic nanoparticles, comparisons with other types of carbonaceous electrodes will be made just like edge or basal plane pyrolytic graphite . After selection of the best experimental conditions the analytical parameters will be investigated, namely range of linear response, sensitivity, limits of detection, reproducibility and repeatability. Effects of potential interfering and study addition and recovery will also be evaluated.
News published in Agência FAPESP Newsletter about the scholarship: