SCANNING TUNNELING MICROSCOPIC ROUGHNESS STATISTICS ON THE ELECTROCHEMICAL QUARTZ MICROBALANCE

Morphological changes and reconstructions of metallic electrode surfaces can prevent direct monitoring of the molecular organization in the electrochemical double layer by means of the electrochemical quartz microbalance (EQMB). Roughness can feign mass changes by carrying electrolyte in surface pockets. There are contradictory results from EQMB, charge, and scanning electron microscopy morphology investigations. We resolved these problems by a statistical evaluation of scanning tunneling microscopic images at gold surfaces emersed at relevant potentials. No roughness change was observed in the hydroxide monolayer potential region because this is thermodynamically more favourable, especially in base, than growth of a three-dimensional hydroxide layer involving molecular place exchange connected with roughening.