Electrocatalytic oxidation of methanol on Ru deposited NiZn catalyst at graphite in alkaline medium


Telli E., Doner A., KARDAŞ G.

ELECTROCHIMICA ACTA, cilt.107, ss.216-224, 2013 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

The methanol oxidation on C/NiZn-Ru electrode in a 1.00 M KOH and 1.00 M KOH + 1.00 M methanol solutions at different scan rates and temperatures was studied by the cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) techniques. The graphite electrode is coated in a nickel-zinc bath by electrodeposition for use as anode materials for methanol oxidation in alkaline solutions. It is etched in a concentrated alkaline solution to produce a porous and electrocatalytic surface suitable for use in the methanol oxidation (C/NiZn). Ruthenium was electrodeposited on a C/NiZn electrode. The surface morphologies and compositions of electrodes were determined by energy dispersive X-ray (EDX) and scanning electron microscopy (SEM). Kinetic parameters of oxidation such as the anodic electron transfer coefficient (alpha(a)), cathodic electron transfer coefficient (alpha(c)), charge transfer rate constant (k(s)) and activation energy values were calculated. The effect of methanol concentration on methanol oxidation were also investigated. It was found that the ruthenium electrodeposited electrode showed higher catalytic activity and stability toward methanol oxidation than the C/NiZn electrode. (C) 2013 Elsevier Ltd. All rights reserved.