Abstract
In this work, the studied Nickel Schiff-base complex was synthesized in methanol medium using dehydroacetic acid ( DHA), ethylene diamine in presence of an excess of pyridine and tetrahydrate salt of nickel chloride. The properties of this new complex were determined via infrared ( IR), electronic spectrum (UV-Vis.), elemental analysis (CHN), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). The synthesized nickel monomer was electrodeposited on glassy carbon (GC), Indium tin oxide (ITO) and fluorine tin oxide (FTO) as conductive electrodes by anodic oxidation in alkaline solutions yielding electroactive films strongly adhered. These materials, currently called modified electrodes (noted ME), were obtained by the successive cycling at the appropriate potentials showing a typical voltammetric response such as Ni(III)/Ni(II) redox couple. Accordingly, the poly-[Ni(II)- L-pyridine]Cl modified electrodes were characterized by cyclic voltammetry whereas the surface morphology of these films was characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The films prepared onto glassy carbon electrode display a powerful and persistent indirect catalytic activity towards the electro-oxidation of some aliphatic alcohols of short chain. The electro-oxidation reaction of methanol (MeOH), ethanol (EtOH) and iso-propanol (iPrOH) has been investigated by cyclic voltammetry and change with the number of voltammetric scans and concentrations of the used alcohol. A virtuous electrocatalytic activity was obviously observed showing that the oxidation reaction was illustrated by a peak current which increases progressively as the alcohol concentration increases.