Nanoparticles agglomeration tendency

Transmission electron microscope ( ) images of such n-Al powders indicate the presence of a thin passivation layer of aluminum oxide (A1203) which provides stability to it in the air. Without this layer, A1 nanoparticles would be pyrophoric and also have tendency to agglomerate to form bulk A1 metal. In order to protect this n-Al powder further, some researchers have suggested its coating with self-assembled nanolayers using perfluoroalkyl carboxylic acid [90]. 

Morphology evolution is thus found to be dependent on the processing technique applied to disperse the nanoparticles. The latex-blended and prevulcanized nanocomposites show predominant exfoliation with some intercalation, especially in uncured and prevulcanized samples. In conventionally cured but latex-blended nanocomposites, realignment of NA particles is visible, with a greater tendency of NA platelets towards agglomeration. In solid state mixing, the dispersion is still poorer. XRD studies also corroborate the above observations. 

Synthesis of nanomaterials is not simple due to their thermodynamic and kinetic tendency of particle to agglomerate into bulk particles due to high surface energies. For the synthesis of nanomaterial, it is necessary to know the mechanism for the change of molecular precursor to their final materials. The soft chemical approach in nanoscience leads to the synthesis of fairly monodispersed nanoparticle and the non-aggregated nanoparticle is no longer a constraint for bulk production in material science. 

How to stabilize the metal particles on the support. The metal particles on supports, like carbon powder or carbon nanotubes, undergo agglomeration or detach from the support. This is because the nanoparticles are active and mobile— and thus have a tendency to agglomerate together—and there are no chemical bonds between the particles and the support. It is necessary to structure the support in such a way that allows the metal particles to anchor tightly on the surface of the support. 

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