5-nm Bucky Diamond: An Emerging Nanocarbon

Primary cubic diamond crystals with an average particle‐size of 4.7±0.6 nm are now available in quantities. They are prepared by disintegrating crude agglutinated products of detonation nanodiamond by means of beads‐milling. Although purification to atomistic precision has not been achieved, interesting behaviors of the first typical nanocarbon particle are being unveiled quickly. For example, contrary to expectation from chemical knowledge, the single‐nano diamond particles are ‘soluble’ in water to give stable colloidal solution. SCC‐DFTB calculations on smaller models suggest spontaneous electron migration from diamond core to fullerenic shell, supposed to have been formed by spontaneous diamond‐graphite rearrangement. Complex geometrical and electronic structures endow each particle of single‐nano diamond with high functionality of its own. Another remarkable feature is the number effect: astronomical number of functional single‐nano particles exists in very small weight: 1 g of our nanodiamond contains 6.15×1018 particles. This means that only tiny amounts of nanoparticles will show enormous effect.