The scheme of methanol oxidation at a platinum electrode in an acid solution

Abstract

The scheme of methanol oxidation at a platinum electrode in a sulphuric acid solution was investigated by potential step and product-analysis methods. The potential step method revealed that dissolved formaldehyde accumulated in the vicinity of the electrode surface during methanol oxidation at potentials of about 0.6–0.8 V. Its accumulation occurred also at low methanol concentrations at which the bulk concentration of the formaldehyde was small. The rates of formaldehyde oxidation obtained and its accumulation showed that carbon dioxide was formed predominantly via dissolved formaldehyde at about 0.75–0.80 V, while at lower potentials its formation did not occur via dissolved formaldehyde. High methanol concentrations favoured the accumulation of formaldehyde in the bulk solutions.