Nanoparticles ordered growth

Figure 11.8 Formation of ordered nanoparticles of metal from diblock copolymer micelles, (a) Diblock copolymer (b) metal salt partition to centres of the polymer micelles (c) deposition of micelles at a surface (d) micelle removal and reduction of oxide to metal, (e) AFM image of carbon nanotubes and cobalt catalyst nanoparticles after growth (height scale, 5 nm scan size, lxl pm). [Part (e) reproduced from Ref. 47].

In order to eliminate columnar structures it is necessary to increase the migration ability of atoms and molecules on the surface and also to remove the involvement of clusters in the process of growth. To prevent the participation of clusters and nanoparticles during growth and in order to create the conditions for highly perfect ZnO layers s mthesis, we explored the possibility of ZnO layers growth according to VLS-model. 

The basic principle of chemical synthesis of nanoparticles is to initiate chemical reactions and control the nu-cleation and growth of the reaction products. In order to achieve monodispersity, LaMer has shown that the separation of the nucleation stage from the growth stage is an important factor to be considered (Figure 1). 

Microporous nanoparticles with ordered zeolitic structure such as Ti-Beta are used for incorporation into walls or deposition into pores of mesoporous materials to form the micro/mesoporous composite materials [1-3], Microporous particles need to be small enough to be successfully incorporated in the composite structure. This means that the zeolite synthesis has to be stopped as soon as the particles exhibit ordered zeolitic structure. To study the growth of Ti-Beta particles we used 29Si solid-state and liquid-state NMR spectroscopy combined with x-ray powder diffraction (XRPD) and high-resolution transmission electron microscopy (HRTEM). With these techniques we monitored zeolite formation from the initial precursor gel to the final Ti-Beta product. 

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