High catalytic activity of chemically activated gold electrodes towards electro-oxidation of methanol

Electro-oxidation of methanol has been investigated on activated, rough gold electrodes in alkaline solutions. The electrodes were activated by formation and decomposition of gold amalgam. The oxidation of methanol starts at potentials about 400 mV less positive as compared with smooth poly and single crystal gold electrodes and the oxidation Current is much higher. For freshly prepared, activated gold electrodes the oxidation Current is similar to that obtained oil smooth platinum, however it diminishes with time. The formation of small crystallites, which Could trap OH- anions, seems to be the most important factor for this unusual catalytic activity. The dependence of the oxidation process on electrode topography is discussed. (C) 2004 Elsevier Ltd. All rights reserved.