Colloidal electro-optics in nanotechnology research: Characterization of composite nanoparticles

COLL 152

Stoyl P. Stoylov1, Maria Buleva1, Galina Bila2, and Ivana B. Petkanchin1. (1) Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria, (2) Institute of Biocolloid Chemistry, Ukrainian Academy of Sciences, Kiev 03142, Ukraine
Recently, nanocomposites and hybrid nanoparticles have attracted the attention of investigators. This concerns their formation to obtain materials with desired properties and methods for their characterization. Determination of the surface electric properties (dipole moments), the optical anisotropy and size distribution of nanocomposite particles would help clarify the processes of their formation and would advance the development of on-line control for their production. In composite particles, adsorption of small and/or spherical particles on larger anisometric particles renders the former particles accessible to electro-optical characterization. Thus it becomes possible to attack some fundamental problems such as the mechanisms of build-up of permanent dipole moment and slow electric polarizability, and the mechanism of electrical charging of nanoparticles as well. Experimental results, obtained on ferric oxide/silica nanoparticles, illustrate the utility of electro-optic methods for characterizing such objects. These methods are extremely useful in following the “construction” of composite and/or hybrid nanoparticles.
 

Colloidal and Molecular Electro-Optics

Division of Colloid and Surface Chemistry
The 225th ACS National Meeting, New Orleans, LA, March 23-27, 2003