We systematically discuss frictional properties occurring in atomic-force microscope (AFM) tip on graphite system, the graphite/C
60/graphite system, and the C
60 intercalated graphite system. Several possible mechanism to induced superlubricity of C
60 intercalated graphite system are proposed and discussed. It can be expected that the superlubricity is induced by internal sliding between close-packed C
60 monolayers and graphite layers. Our results propose one of the simple guidelines of designing practical superlubric system—reduction of the contact area between intercalated C
60 and graphite sheet to the point-like contact. We anticipate our novel lubrication system to be a startpoint for developing more practical superlubricant using intercalated graphite, which will contribute to solving the energy and environmental problems.
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