Deposition of cobalt nanoparticles on reduced graphene oxide and the electrocatalytic activity for methanol and ethanol oxidation

Abstract

The Cobalt nanoparticles were deposited on reduced graphene oxide (RGO) by electroless plating procedure, in which the RGO was used as substrate precursor. The surface morphology of Co-Pd/Sn/RGO composite was studied by High resolution transmission electron microscopy (HRTEM) and Field emission scanning electron microscopy (FESEM). The Powdered x-ray Diffraction studies (PXRD) and also Raman Spectroscopy (RAMAN) have shown the Cobalt deposition on RGO. The extent of deposition of Cobalt nanoparticles on RGOs including the under coat elements such as Tin and Palladium was studied by Energy dispersive x-ray analysis (EDX) and x-ray Photoelectron Spectroscopy (XPES) techniques. The electrocatalytic activity of the deposited cobalt nanoparticles on RGO has been tested by Cyclic voltammetry (CV) and Impendence spectroscopy studies (EIS). The effective surface areas of Co-Pd/Sn/RGO and RGO were calculated using Randles-Sevecik equation and the values are 6.0785 × 10−6 cm2 and 1.588 × 10−6 cm2 respectively. The electrocatalytic property of Co-Pd/Sn/RGO has been tested for energy application by the oxidation of methanol and ethanol. A significant electrocatalytic activity of Co-Pd/Sn/RGO has been found for the oxidation of methanol and ethanol in acidic medium. These results suggest that the Co-Pd/Sn/RGO material could be harnessed as electrode/catalyst system for alcohol fuel cell application.