Co–Au core-shell nanocrystals formed by sequential ion implantation into SiO2

P. Kluth, B. Hoy, B. Johannessen, S. G. Dunn, G. J. Foran, M. C. Ridgway
2006 Applied Physics Letters  
Co-Au core-shell nanocrystals ͑NCs͒ were formed by sequential ion implantation of Au and Co into thin SiO 2 . The NCs were investigated by means of transmission electron microscopy and extended x-ray absorption fine structure spectroscopy. The latter reveals a bond length expansion in the Co core compared to monatomic Co NCs. Concomitantly, a significant contraction of the bond length and a significant reduction of the effective Au-Au coordination number were observed in the Au shells.
more » ... Au shells. Increased Debye-Waller factors indicate significant strain in the NCs. These experimental results verify recent theoretical predictions.
doi:10.1063/1.2360891 fatcat:skqckeu4obcsjgtjctq5wk5xim