Electrocatalytic Oxidation of 1-Propanol and 2-Propanol on Electro-active Films Derived from NiII-(N,N′-bis(2-Hydroxy, 3-Methoxy Benzaldehyde)-1,2-Propandiimine) Modified Glassy Carbon Electrode

Complexes of NiII–(N,N′-bis(2-hydroxy, 3-methoxy benzaldehyde)-1,2-propandiimine) can be electro-polymerized onto GC electrode in an alkaline solution to give an electro-active film strongly adhered on the electrode surface. In alkaline solution, this poly-(NiII{sal-1,2-pn(3-OMe)2})/GC film shows the typical voltammetric response of a surface-immobilized redox couple, as can be anticipated for the Ni2+/Ni3+ transitions into the film. In addition, the film exhibits a potent and persistent electro-catalytic activity towards the oxidation of 1- and 2-propanol. In CV studies, in the presence of these alcohols, poly-(NiII{sal-1,2-pn(3-OMe)2})/GC electrode shows a new oxidation peak for the alcohols at a potential much more positive than the oxidation peak potential of NiII species. Based on a proposed mechanism, NiIII sites act as active surface for the direct electro-oxidation of alcohols. The corresponding rate laws have been derived, and the kinetic parameters have been obtained. Also, an amperometric procedure has been successfully applied to the determination of the alcohols.