Co nanodisks

Figure 6 TEM image of partially self-assembled Co nanodisks. Bar = 100 nm. (Reprinted with permission from Ref 157 2002 American Chemical Society)...

Figure 3.126 TEM partially self-assembled Co nanodisks. Scale bar= 100nm. Reproduced with...

Figure4.41 TEM imageofstackedface-to-face Tilting direction corresponds with the hcp-Co nanodisks. The pictures on the left double arrows. Reproduced from Ref. [105], correspond to no tilt and those on the right the Copyright2002, with permission from American pictures on the right 25° tilt. The bar is 200 nm. Chemical Society.

Figure 2 TEM micrographs of (a) hcp-Co self-assembled nanodisks (bar= 100nm) and (b) Fe nanorods respeotively obtained by thermolysis of cobalt and iron oarbonyl oomplexes7 Reproduoed with permission from ACS Publioations.

Similarly, using the same particles as those used for the synthesis of CdS QDs (see Sect. 6.2, Fig. 36), silver nanoparticles could be deposited onto carboxylated poly(MMA-co-MAA) particles using silver salts as precursors [315, 316]. As for the case of CdS, periodic structures of polymer/silver hybrid colloids were elaborated. The method obviously opens a new avenue for production of optically responsive materials with a controlled periodicity. In another work using commercial llOnm carboxylate-functionalized PS particles as templates, Hao et al. reported the synthesis of silver nanodisks formed through chemical reduction of silver salts in DMF [332]. The composite particles obtained (Fig. 39) exhibited an intense electronic spectrum differing markedly from those of spheres. Still using... 

Cobalt nanodisks have also been prepared by the same method and the same precursor in the presence of rhodamine (RhB) and HDA. The bulkiness of RhB, which hinders its adsorption on the Co surface in the early growth stages as well as the specific adsorption of HDA at the 0001 facets, is responsible for this peculiar growth mode. An out-of-plane magnetization was observed. These nano-objects self-assemble into ID chains with high magnetic anisotropy [59]. 

While the microemulsion method has been widely applied to the production and stabilization of spherical metal particles with various sizes and compositions, shape control of noble metallic particles using this procedure has only been demonstrated in a handful of studies to date. Pileni and co-workers demonstrated that it is possible to control nanocrystal shape to some extent within microemulsions.Although the shape of the templates plays a role during the growth of the nanocrystals, these authors showed that the particle shape can be controlled even if the microscopic structure of the self-assembled surfactant system used as a template remains unchanged and that addition of salt to the templates can induce drastic changes in the particle shape. Recently, the same group also reported the synthesis of silver nanodisks in reverse micellar solution by reduction of Ag(AOT) with hydrazine, with various sizes that depended on the relative amount of hydrazine, but with constant aspect ratio. 

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