  Defects induced by liquid-phase exfoliation of graphite using sonication were
studied. It was shown that localized impact by cavitation shock waves can
produce bulk ripplocations and various types of dislocations in graphite
nanoplatelets. Formation of ripples is more pronounced in large aspect
(length/width) ratio platelets or nanobelts. Quasi-periodical ripple systems
were observed in many nanobelts after sonication. Mechanism of formation of
ripples and dislocations during sonication was proposed. Surprisingly, fast
high-temperature processing was found to anneal most of defects. This is
consistent with our observations that defects associated with ripplocations are
strongly localized and thus can be fast annealed.
