Superperiodic Structures of Highly Oriented Pyrolytic Graphite Observed by Scanning Tunneling Microscopy

The superperiodic structures of highly oriented pyrolytic graphite(HOPG) have been observed by scanning tunneling microscopic(STM).This superperiodic structure had a spacing ranging from 2.4 to 5.7 nm with peak-to-peak amplitudes out of plane extending from 1.0 to 3.8 ?,and an orientation of about 30° with respect to the atomic corrugation.We proposed that this might be due to the graphite interlayer rotational alignment caused by the intercalation of electrolytes and solvents into the base plane of HOPG surface.