Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1276458 | International Journal of Hydrogen Energy | 2016 | 11 Pages |
•Pt and Pt–Ru supported PEDOT–RGO nanocomposites are prepared by electrochemical method.•Their electrocatalytic activity for methanol oxidation is assessed with respect to PEDOT/Pt and RGO/Pt.•PEDOT–RGO/Pt has a high specific surface area and shows the best performance.•The effects of Pt loading, methanol concentration and electrode stability are studied.•The kinetics of methanol oxidation at variable Ru loading is investigated.
The electrocatalytic performance of reduced graphene oxide-poly(3,4-ethylenedioxythiophene)/platinum (RGO–PEDOT/Pt) nanocomposite for methanol oxidation has been evaluated with respect to PEDOT/Pt and RGO/Pt. The electrocatalysts are characterized by scanning electron microscopy, transmission electron microscopy and cyclic voltammetry. The RGO–PEDOT/Pt has been found to have favorable characteristics in terms of large specific surface area (460.5 m2 g−1) and small particle size (0.61 nm). The methanol oxidation current for RGO–PEDOT/Pt is nearly 3.6 and 12.6 times higher than that for PEDOT/Pt and RGO/Pt respectively. Among the three electrocatalysts, the RGO–PEDOT/Pt nanocomposite shows the best electrocatalytic behavior towards methanol oxidation with a mass specific peak current of 774 mA mg−1 cm−2 for a Pt loading of 191.4 μg cm−2 at a concentration of 1 M methanol in 0.5 M H2SO4. The effects of Pt loading, methanol concentration and electrode stability have been studied. RGO–PEDOT/Pt–Ru electrodes with a fixed Pt and variable Ru ion concentrations are prepared by chronoamperometry and the Pt–Ru alloy formation was confirmed by X-ray diffraction method. The electrocatalytic performance of the Pt–Ru supported RGO–PEDOT for the oxidation of methanol is evaluated by cyclic voltammetry. The Tafel kinetic analysis indicates that the RGO–PEDOT/Pt–Ru prepared with equal concentrations of Pt and Ru ions (i.e. RGO–PEDOT/Pt–Ru (1:1)) gives the best performance in terms of the lowest onset potential (0.14 V), highest exchange current density (2390 μA cm−2) and highest If/Ir ratio (2.33) implying minimum poisoning.