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arXiv · 0806.4644

Diffusional Nucleation of Nanocrystals and Their Self-Assembly into Uniform Colloids

Abstract

We review theoretical explanation of mechanisms of control of uniformity in growth of nanosize particles and colloids. The nanoparticles are synthesized as nanocrystals, by burst nucleation from solution. The colloids are self-assembled by aggregation of these nanocrystals. The two kinetic processes are coupled, and both are driven by diffusional transport. The interrelation of the two processes allows for formation of narrow-size-distribution colloid dispersions which are of importance in many applications. We review a mathematical model of cluster growth by capture of diffusing "singlets." Burst nucleation of nanoparticles in solution is then analyzed. Finally, we couple it to the secondary process of aggregation of nanoparticles to form colloids. We address aspects of modeling of particle size distribution, as well as other properties.

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Vladimir Privman. 2008-06-30. Diffusional Nucleation of Nanocrystals and Their Self-Assembly into Uniform Colloids. https://arxiv.org/abs/0806.4644

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