Thermodynamical predictions of nanodiamonds synthesized by pulsed-laser ablation in liquid

Based on the nanothermodynamical approach, we performed the thermodynamical predictions of nanodiamonds synthesized by pulsed-laser ablation in liquid. The nanothermodynamical analyses showed that the formation of nanodiamonds with sizes of 3-5 nm would be preferable to that of large nanodiamonds in the pressure-temperature region of 10-15 GPa and 4000-5000 K created by pulsed-laser ablation of a graphite target in water in the carbon phase diagram. Meanwhile, the probabilities of the phase transition from graphite to diamond are calculated to be rather high, up to 10(-3)-10(-2) in the same pressure-temperature region. These theoretical results indicate that pulsed-laser ablation in liquid is expected to be an effective industrial route to synthesize ultrananocrystalline diamonds. (C) 2005 American Institute of Physics.