Transparent nanocrystalline diamond ceramics fabricated from C-60 fullerene by shock compression

Transparent nanocrystalline diamond ceramics, consisting of a few nanometer-sized diamond crystallites that an unstable in themselves because of higher surface energy, were fabricated successfully from C-60 fullerene using a shock compression and rapid quenching technique. The platelets were transparent and very hard, nearly comparable to type IIa diamond. Transmission electron microscopy and electron energy loss spectroscopy revealed that individual crystallites had combined directly or through a very thin and modified sp(3) carbon layer, which possibly stabilized the nanometer-sized crystallites, The size order and sp(3) configuration of the nanotexture caused the transparency and hardness of the present material. (C) 1997 American Institute of Physics.