Ion implantation in nanodiamonds: size effect and energy dependence
  Nanoparticles are ubiquitous in nature and are increasingly important for
technology. They are subject to bombardment by ionizing radiation in a diverse
range of environments. In particular, nanodiamonds represent a variety of
nanoparticles of significant fundamental and applied interest. Here we present
a combined experimental and computational study of the behaviour of
nanodiamonds under irradiation by xenon ions. Unexpectedly, we observed a
pronounced size effect on the radiation resistance of the nanodiamonds:
particles larger than 8 nm behave similarly to macroscopic diamond (i.e.
characterized by high radiation resistance) whereas smaller particles can be
completely destroyed by a single impact from an ion in a defined energy range.
This latter observation is explained by extreme heating of the nanodiamonds by
the penetrating ion. The obtained results are not limited to nanodiamonds,
making them of interest for several fields, putting constraints on processes
for the controlled modification of nanodiamonds, on the survival of dust in
astrophysical environments, and on the behaviour of actinides released from
nuclear waste into the environment.
