Journal of Electroanalytical Chemistry, Vol.399, No.1-2, 83-89, 1995
STM Investigation of Hopg Superperiodic Features Caused by Electrochemical Pretreatment
The surface topography of highly oriented pyrolytic graphite (HOPG) which has been subjected to anodized treatment at a low potential (less positive) has been exhaustively studied using scanning tunneling microscopy (STM). Characterization of graphite surface has revealed that a small percentage of the surface (5%-10%) shows superperiodic features. In this case, the typical topographical features are triangular networks with the observed periodicities in the plane ranging from approximately 26 to 240 nm with peak-to-peak amplitudes out of the plane extending from 7 to 35 Angstrom. We show that this triangular network can be attributed to the injection of electrolyte and solvent in the earliest stages of oxidation of the basal HOPG electrode surface. A simple model is proposed to explain this phenomenon.
Keywords:GLASSY-CARBON ELECTRODES;SCANNING-TUNNELING-MICROSCOPY;ORIENTED PYROLYTIC-GRAPHITE;ANODIC-OXIDATION;SURFACE;INTERCALATION;ACTIVATION