Nucleation Control in the Aggregative Growth of Bismuth Nanocrystals

• Published in: Chemistry of materials Vol. 23; no. 2; pp. 137 - 144
• Main Authors: Richards, Vernal N, Shields, Shawn P, Buhro, William E
• Format: Journal Article
• Language: English
• Published: American Chemical Society 25-01-2011
• Subjects: Crystal Growth; Nanomaterials (Nanops, Nanotubes, etc.); Theory and Modeling
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm101957k

The kinetics and mechanism of Bi-nanocrystal growth from the precursor Bi[N(SiMe3)2]3 are determined at various Na[N(SiMe3)2] additive concentrations. The results establish that aggregative nucleation and growth processes dominate Bi-nanocrystal formation. The time dependence of the aggregative nucleation rate−the nucleation function−is determined over the range of Na[N(SiMe3)2] concentrations studied. The time width of aggregative nucleation (Δt n) is shown to remain reasonably narrow, and to correlate with the final Bi-nanocrystal size distribution. The maximum aggregative nucleation rate (Γmax) is shown to vary systematically with Na[N(SiMe3)2] concentration, producing a systematic variation in the final nanocrystal mean size. The Na[N(SiMe3)2] additive functions as both a nucleation-control agent and an Ostwald-ripening agent.