Onion-like carbon from ultra-disperse diamond
نویسندگان
چکیده
A new material containing macroscopic quantities of onion-like carbon (OLC) particles is produced by heat treatment of ultra-disperse diamond (UDD) powder (2-6 nm). Annealing products (characterized by high-resolution electron microscopy) are presented by: (a) quasi-spherical particles with closed concentric graphite shells, (b ) polyhedron particles with closed shells, (c) elongated particles with linked external graphite-like layers and closed quasi-spherical internal shells. The intermediates of UDD transformation have been registered. The structural transformation of UDD begins from the surface of the diamond particles towards a crystal bulk. The transformation rate of ( 111) diamond planes to graphite-like sheets is higher than that of other planes.
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