Fabrication and characterization of non-platinum electrocatalyst for methanol oxidation in alkaline medium: Nickel nanoparticles modified carbon-ceramic electrode

摘要

The use of carbon-ceramic electrode (CCE) modified with nickel nanoparticles was studied for the electrocatalytic oxidation of methanol in alkaline medium by cyclic voltammetry and chronoamperometry. After preparation of the carbon-ceramic by sol-gel technique as the electrode matrix, its surface was potentiostatically coated with Ni nanoparticles at -600 mV vs. SCE in an aqueous solution of 0.1 M Na_2SO_4 (pH = 3.8) containing 5 mM NiCl_2. The CCE modified with nickel nanoparticles (CCE/Ni) was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and cyclic voltammetry and used as electrocatalyst for oxidation of methanol in alkaline solution. It was shown that the CCE/Ni was the most efficient catalyst in the oxidation of methanol making it more attractive for fuel cell applications. The effective parameters on electrocatalytic oxidation of methanol such as the Ni loading procedure, amount of Ni loading and methanol concentration were investigated and the results were discussed. Finally, the long-term stability of the modified electrode has also been investigated. Published by Elsevier Ltd on behalf of Professor T Nejat Veziroglu.