An Electrochemical Investigation of Methanol Oxidation on Nickel Hydroxide Nanoparticles

In this work, a nickel-modified glassy carbon electrode (GCE) was prepared using a potentiostatic method in 0.1 M acetate buffer solution at pH 4.0 containing 1.0 mM nickel nitrate. Nickel hydroxide nanoparticles were prepared using consecutive potential scanning in 0.1 M NaOH solution. The as-prepared catalyst was characterized by field emission scanning electron microscopy and electrochemical methods. Electrochemical characterization exhibited stable redox behaviour of the Ni(III)/Ni(II) couple. Cyclic voltammetric experiments showed that electrocatalytic oxidation of methanol can occur at the modified electrode, whereas it is not observed at a bare GCE. The effect of potential sweep rates and methanol concentration on its electrochemical behaviour was studied. The rate constant (k) for the chemical reaction between methanol and catalytic centres has been evaluated by chronoamperometry. In addition, long-term stability of the modified electrode was investigated by electrochemical methods.