A simple method to produce almost perfect graphene on highly oriented   pyrolytic graphite
  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. 
M. J. Webb, P. Palmgren, P. Pal, O. Karis, and H. Grennberg
cond-mat.mtrl-sci