  A simple and effective stepwise-method has been developed to remove defects
from the top graphene layers of highly orientated pyrolytic graphite. Using a
combination of ozone exposure and moderately high temperature we have shown
that a defect-rich graphite surface can be modified to generate a graphene-like
surface containing a negligible amount of oxygen, hydrogen and sp3 carbon. We
report definitive x-ray photoelectron and x-ray absorption spectroscopy
analysis after each stage of the process, suggest a mechanism by which the
modification occurs and propose it as a route towards the preparation or
manipulation of pristine graphene samples.
