AN ELECTROCHEMICAL QUARTZ-CRYSTAL MICROBALANCE INVESTIGATION OF THE ADSORPTION AND OXIDATION OF CO ON A PLATINUM-ELECTRODE

The adsorption and electrocatalytic oxidation of carbon monoxide on pl atinum was studied in both acid and alkaline supporting electrolytes u sing an electrochemical quartz crystal microbalance. Depending on the pH of the medium, a significant influence of CO on the electrode mass was observed, particularly in the potential range preceding the comple te oxidation of CO. In acid medium coupling with solvent molecules was also evidenced and was found to be potential dependent. Furthermore, the mass responses depended strongly on the way the adsorption of CO w as realised. In addition, the effect of the bulk concentration of CO w as investigated in the case of perchloric acid medium. Copyright (C) 1 996 Elsevier Science Ltd.