Abstract
Molecular dynamics (MD) simulations are used
to show that a spherical zinc blende (ZB) nanocrystal (NC)
can transform into a tetrapod or an octapod as a result of
heating, by a local zincblende-to-wurtzite phase transformation
taking place in the NC. The partial sphere-to-tetrapod or
sphere-to-octapod transition occurs within simulation times of
30 ns and depends on both temperature and NC size.
Surprisingly, the wurtzite (WZ) subdomains are not formed
through a slip mechanism but are mediated by the formation
of highly mobile Cd vacancies on the ZB{111} Cd atomic planes. The total potential energy of a tetrapod is found to be lower
than that of a ZB sphere at the same numbers of atoms. The simulation results are in good agreement with experimental highresolution
transmission electron microscopy (HR-TEM) data obtained on heated colloidal CdSe NCs.
to show that a spherical zinc blende (ZB) nanocrystal (NC)
can transform into a tetrapod or an octapod as a result of
heating, by a local zincblende-to-wurtzite phase transformation
taking place in the NC. The partial sphere-to-tetrapod or
sphere-to-octapod transition occurs within simulation times of
30 ns and depends on both temperature and NC size.
Surprisingly, the wurtzite (WZ) subdomains are not formed
through a slip mechanism but are mediated by the formation
of highly mobile Cd vacancies on the ZB{111} Cd atomic planes. The total potential energy of a tetrapod is found to be lower
than that of a ZB sphere at the same numbers of atoms. The simulation results are in good agreement with experimental highresolution
transmission electron microscopy (HR-TEM) data obtained on heated colloidal CdSe NCs.
| Original language | English |
|---|---|
| Pages (from-to) | 5869−5876 |
| Journal | Journal of the American Chemical Society |
| Volume | 135 |
| DOIs | |
| Publication status | Published - 2013 |