On the thermodynamic path enabling a room-temperature, laser-assisted graphite to nanodiamond transformation

• Published in: Scientific reports Vol. 6; no. 1; p. 35244
• Main Authors: Gorrini, F., Cazzanelli, M., Bazzanella, N., Edla, R., Gemmi, M., Cappello, V., David, J., Dorigoni, C., Bifone, A., Miotello, A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12.10.2016; Nature Publishing Group
• Subjects: 140/133; 639/301; 639/925/357/551; Atmospheric pressure; Graphite; Humanities and Social Sciences; Lasers; multidisciplinary; Nucleation; Optics; Science; Temperature effects; Temperature requirements
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep35244

Nanodiamonds are the subject of active research for their potential applications in nano-magnetometry, quantum optics, bioimaging and water cleaning processes. Here, we present a novel thermodynamic model that describes a graphite-liquid-diamond route for the synthesis of nanodiamonds. Its robustness is proved via the production of nanodiamonds powders at room-temperature and standard atmospheric pressure by pulsed laser ablation of pyrolytic graphite in water. The aqueous environment provides a confinement mechanism that promotes diamond nucleation and growth, and a biologically compatible medium for suspension of nanodiamonds. Moreover, we introduce a facile physico-chemical method that does not require harsh chemical or temperature conditions to remove the graphitic byproducts of the laser ablation process. A full characterization of the nanodiamonds by electron and Raman spectroscopies is reported. Our model is also corroborated by comparison with experimental data from the literature.