Nickel-dimethylglyoxime complex modified graphite and carbon paste electrodes: preparation and catalytic activity towards methanol/ethanol oxidation

Abstract

Nickel-dimethylglyoxime complex (abbreviated as Ni(II)(DMG) 2 ) modified carbon paste and graphite electrodes were prepared by mixing Ni(II)(DMG) 2 with graphite paste, and coating Ni(II)(DMG) 2 to the graphite surface. It is necessary to cycle the electrode potential to a high value (e.g. 0.8 V versus SCE) for the preparation of the modified electrodes. The electrochemical reaction was originally assumed to be a one-electron process converting Ni(II)(DMG) 2 toNi(III)ONi(III)(OH)(DMG) 2 ] -showed a strong catalytic activity toward electro-oxidation of methanol and ethanol. The electrocatalytic oxidation currents consistently increase with the increase in Ni(II)(DMG) 2 loading, OH -, and alcohol concentrations. Rotating disk electrode results obtained with a Ni(II)(DMG) 2 coated graphite disk electrode showed that the electrocatalytic oxidation of alcohol is a 4-electron process producing formate anion (methanol oxidation) or acetate anion (ethanol oxidation). A mechanism for the electrocatalytic oxidation of methanol/ethanol was proposed, and a rate-determining step was also discussed.

Dimethylglyoxime based ion-imprinted polymer for the determination of Ni(II) ions from aqueous samples

“…The IR spectrum of the Ni(II)-DMG IIP (as shown in Fig. 5C) also shows the presence of an OH deformation band at 1 737 cm -1 , indicating the formation of a hydrogen bridge (Burger et al, 1965;Cardoso et al, 2009;Nyquist et al, 2001;Panja et al, 1991). This hydrogen bridge confirms the formation of the red square planar Ni(II)-DMG IIP complex and is absent in the DMG and in the NIP (as shown in Figs.…”

Nickel and cobalt oxide composite as a possible electrode material for electrochemical supercapacitors

“…Based on the electron transfer and OH À ion numbers obtained above, the following redox reaction for Ni 0.37 Co 0.63 (OH) 2 in alkaline solution is proposed as Eq. (6) [46].…”

Cetyltrimethyl ammonium bromide effect on highly electrocatalysis of methanol oxidation based on nickel particles electrodeposited into poly (m-toluidine) film on the carbon paste electrode

“…It is generally agreed that the Ni-based catalysts such as nickel oxides (hydroxides) and complexes in a basic aqueous medium can catalyze methanol oxidation through an overall four electron process producing formate anion [27]:…”