Electrooxidation of Methanol and Ethanol in Alkaline Solutions on Modified Platinum Electrode

Abstract

This work aims to activate a platinum electrode by repetitive cyclic electrochemical polarization of smooth platinum in alkaline solutions. The resultant modified electrode has been tested as an electro-catalyst for oxidation of candidate fuels, viz. methanol and ethanol. A comparison has been made between the two alcohols with regard to the kinetics of their electro-oxidation. The effect of several kinetic variables has been reported. The results reveal that the modified platinum electrode is a good catalyst for their electro-oxidation in alkaline media. The advantage of this surface is the inhibition of poisoning of Pt by CO intermediate. Change of charge density with number of cycles reveals the extent of increase of surfaces activation is due to increase of surface roughness. The onset potential for the electrooxidation of ethanol is less than that of methanol on the developed surface. Electro-oxidation in 0.05 M KOH is more feasible than in 0.1 M KOH possibly due to the less adsorption of the hydroxyl ion.

Estimation of Cell Voltage and Power Density for Alcohols Electro-Oxidation on Modified Platinum Surface

“…The details of the experiments is given elsewhere [4]. As working electrode, pure platinum (0.6 and 0.4 cm 2 as a sheet, Aldrich, thermocouple quality) was used.…”

“…Previously the authors of this article had studied the electro-oxidation of simple alcohols on modified platinum electrode [4]. The alcohols are methanol and ethanol.…”