Original scientific paper

Formation Mechanisms of Uniform Colloid Particles

Egon Matijević ; Center for Advanced Materials Processing Clarkson University, Potsdam, NY, USA
Dan Goia ; Center for Advanced Materials Processing Clarkson University, Potsdam, NY, USA

Abstract

The relationship of the shape and structure of uniform colloidal particles to different mechanisms
of formation by precipitation in homogeneous solutions is reviewed. Specifically, conditions
leading to (a) amorphous spheres, (b) nonspherical crystals of different shapes, and (c)
polycrystalline particles of different morphologies including spheres are distinguished. The last
case is observed when larger particles are formed by aggregation of nanosized precursors. It is
now recognized that the latter process is more common than previously understood. A model
explaining the size selection of monodispersed spheres by aggregation is illustrated in the case
of silver particles. It was also demonstrated that uniform polycrystalline particles of other
shapes are generated by the aggregation process. Challenges faced in the effort to develop at
least a semi-quantitative explanation of the shape factor in the latter case are outlined.

Keywords

aggregation mechanism; colloid shape; partcles structures; precipitation

Hrčak ID:

18672

URI

https://hrcak.srce.hr/18672

Publication date:

30.11.2007.

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