POTENTIAL DEPENDENCE OF THE YIELD OF CARBON-DIOXIDE FROM ELECTROCATALYTIC OXIDATION OF METHANOL ON PLATINUM(100)

The yield of complete oxidation product (CO2) from electrocatalysis of methanol on a Pt(100) electrode in perchloric acid electrolyte at roo m temperature was determined by combined measurements of chronoamperom etry and linear sweep voltammetry. The fractional yield of CO2 was zer o over a potential range of 0.35-0.45 V-RHE and increased monotonicall y to unity over the potential range of 0.5-0.65 V. The results may be explained by a simple parallel mechanism, in which methanol oxidizes d irectly to CO2, or by a complex serial mechanism, in which the overpot ential for CO oxidation is reduced by solution phase methanol.