Fig. 2.

a Schematic illustrations of dot-in-rod and dot-in-tetrapod structures obtained from wurtzite and zinc blende seeds, respectively. b Absorption spectrum and TEM image of 4.4-nm CdSe NCs with wurtzite lattice. c TEM image of CdSe-CdS dot-in-nanorod structures. d High-resolution TEM image of a CdSe-CdS dot-in-nanorod grown from a 4.4-nm w-CdSe seed. Scale bar, 5 nm. e High-angle annular dark-field (HAADF) image of a CdSe-CdS dot-in-rod and corresponding elemental profiles for Cd, S, and Se obtained by recording energy dispersion spectroscopy signal intensities along the line shown in yellow in HAADF image. f Absorption spectrum and TEM image of 4.0-nm CdSe nanocrystals with zinc blende lattice. g TEM images of CdSe/CdS tetrapods grown from 4.0-nm zb-CdSe seeds. h TEM image of a CdSe/CdS tetrapod grown from 4-nm zb-CdSe seed. i HRTEM image of a tetrapod fragment showing the interface between {111} planes of zb-CdSe seed and {001} planes of w-CdS arms. Reproduced with permission from Ref. [82]. Copyright 2007, American Chemical Society