Lithium, zinc, silver and gold nanoclusters (NCs) embedded in MgO were created by
means of ion implantation of Li, Zn, Ag and Au ions into single crystals of MgO(100)
and subsequent thermal annealing. Optical, electrical and structural properties of the
NCs were investigated using optical absorption spectroscopy (OAS), high-resolution
X-ray diffraction (XRD) and cross-sectional transmission electron microscopy
(XTEM). The mean nanocluster size is estimated from the broadening of the Mie
plasmon optical absorption bands using the Doyle formula. These results are
compared with the NC size as obtained from XRD (using the Scherrer formula) and
from direct XTEM observations. The three methods are found to be in reasonable
agreement with a mean size of 4.0 and 10 nm found for the Au and Ag clusters,
respectively. Using TEM observations, the relative interface energies of MgO//Au and
MgO//Ag interfaces are also determined. In the case of MgO//Au, they are found not
to be in agreement with theoretical predictions in the literature.
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