Growth and reductive transformation of a gold shell around pyramidal   cadmium selenide nanocrystals
  We report the growth of an unstable shell-like gold structure around dihexagonal pyramidal CdSe nanocrystals in organic solution and the structural transformation to spherical domains by two means: i) electron beam irradiation (in situ) and (ii) addition of a strong reducing agent during synthesis. By varying the conditions of gold deposition, such as ligands present or the geometry of the CdSe nanocrystals, we were able to tune the gold domain size between 1.4 nm to 3.9 nm and gain important information on the role of surface chemistry in hetero nanoparticle synthesis and seed reactivity, both of which are crucial points regarding the chemical design of new materials for photocatalysis and optoelectronic applications. 
Michaela Meyns, Neus G. Bastus, Yuxue Cai, Andreas Kornowski, Beatriz   H. Juarez, Horst Weller, Christian Klinke
cond-mat.mtrl-sci