Potential Dependence and Time Evolution of the Double Layer Structure and Topography of Silver Electrodes Part II: Roughened Silver Films

Abstract

Adsorption / Complex Compounds / Electrochemistry / Surfaces Silver films were electrochemically roughened by oxidation/reduction cycles in different solutions. -Aging of these films in contact with electrolyte solution was monitored for various potentials by means of double layer capacitance measurements. No specifically adsorbable species were present during the aging process. The surface flattening taking place is strongly dependent of the initial microstructure developed during the roughening cycle. -The influence of traces of dissolved oxygen as the main "impurity" was studied in detail. The capacitance/potential curves indicate a pH dependent adsorption/desorption of the superoxide ion 02-. The effect of this process on the mechanism of the 0rreduction is discussed.