Diamond formation by thermal activation of graphite

• Published in: Nature (London) Vol. 402; no. 6758; pp. 162 - 165
• Main Authors: Charlier, J.-C, Palnichenko, A. V, Jonas, A. M, Aronin, A. S, Issi, J.-P
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 11.11.1999
• Subjects: Carbon; Corrosion; Crystals; Diamonds; Graphite; Optics; Thermal energy
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/46000

Synthetic diamond is used in applications ranging from abrasives, tool coatings, bearing surfaces, microelectronics and optics to corrosion protection. The first artificial synthesis used high-pressure techniques to produce diamond as the thermodynamically stable form, but it can also be grown at low pressures as a metastable carbon phase. Here we report the production of high-purity cubic diamond microparticles (10-100 µm), which form in a highly concentrated carbon-vapour phase, followed by deposition of the crystals on the substrate. The carbon-vapour phase is generated by thermal activation of graphite, and the fast initial growth-rates of diamond, in the range 100-500 µm s-1, are at least two orders of magnitude higher than previously reported. We expect that tuning of experimental parameters to optimize the density of the carbon-vapour phase will allow us to grow larger diamond crystals, thereby opening a wider range of potential practical applications.