Anodic Oxidation of Formic Acid at Platinum Electrodes

Abstract

From measurements on electrode potentials and rates of carbon dioxide formation on open circuit and on passing currents, it was concluded that the open‐circuit potential of the , , Pt system is a mixed potential, determined by the direct anodic oxidation of formic acid and the cathodic reduction of hydrogen ion. The value for the exchange current for formic acid oxidation is smaller than 10−10 amp/cm2, and the rates of the mixed reactions on open circuit are between 10−8 and 10−7 amp/cm2. The slope of the potential‐log current curve for the formic acid oxidation is approximately 100 mv per decade of current. It was also concluded that the only effect of platinizing the electrode in this system is to increase the surface area, and that specifically active catalytic sites are not introduced by the platinization process.