In summary, the presence of oxygen and hydrogen atoms on a diamond's surface can significantly influence its chemical properties and reactivity. These atoms can modify the surface characteristics, leading to changes in adsorption behavior and interactions with other molecules, which can be crucial for applications in catalysis and surface science.
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PatrickP2
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Is it true that hydrogen and oxygen atoms on the surface of diamond make it have such a low coefficient of friction?
From the paper "Origin of ultralow friction and wear in ultrananocrystalline diamond" by AR Konicek, DS Grierson, P Gilbert, WG Sawyer, AV Sumant, RW Carpick (Physical review letters, 100, 235502 (2008)):
“The mechanism of low friction supported by this spectroscopy is passivation of dangling bonds [1,3,4,35]. This is the first definitive spectroscopic evidence supporting the passivation hypothesis. This mechanism hinges on a balance between the processes of bond breaking during each sliding pass (which depends on contact stress, sliding rate, and temperature) and passivation by dissociative adsorption of gaseous species, in particular, water vapor (which depends on RH and reciprocation frequency [36,37]).”