Analysis and Interpretation of Scanning Tunneling Microscopy Images in an Electrochemical Environment: Copper on AU(111)
The electrochemical deposition of a copper monolayer on Au(111) has been studied by STM in H2SO4 and Na2SO4 solutions. Three different superstructures, which are attributed to the adsorption of either HSO 4 − , SO 4 2− or both anions, have been observed for the full monolayer. Evidence for the expected epitaxial (1 × 1) overlayer was also obtained at very negative potentials, by avoiding bulk copper growth. A novel STM data analysis by multivariate statistical procedures is shown to provide detailed information, which is not evident in the raw data. The need for a better understanding of the tunneling and imaging mechanisms in an electrochemical environment is emphasized.
KeywordsScanning Tunneling Microscopy Multivariate Statistical Analysis Desorption Peak Scan Tunneling Microscopy Image Electrochemical Environment
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