The author is grateful to the financial support from the Center for Sensing Technology and Research (C-Star) at the University of Arkansas, the joint MRSEC center at the University of Arkansas and Oklahoma University, the Career Award from the NSF DMR, and the NSF grant from the NSF CHE.
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Mechanisms for the Shape-Control and Shape-Evolution of Colloidal Semiconductor Nanocrystals†
Article first published online: 7 MAR 2003
DOI: 10.1002/adma.200390107
© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Additional Information
How to Cite
Peng, X. (2003), Mechanisms for the Shape-Control and Shape-Evolution of Colloidal Semiconductor Nanocrystals. Advanced Materials, 15: 459–463. doi: 10.1002/adma.200390107
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Publication History
- Issue published online: 7 MAR 2003
- Article first published online: 7 MAR 2003
- Abstract
- References
- Cited By
Keywords:
- Growth mechanisms;
- Nanocrystals, semiconductor;
- Nanoparticles, semiconductor;
- Nanorods, semiconductor;
- Shape control
The growth of elongated, one-dimensional (1D) CdSe nanocrystals (see Figure) is found to be a kinetically controlled phenomenon. The 1D growth of wurtzite CdSe proceeds at high monomer concentration following the formation of small tetrahedral “magic-sized” cores of fixed composition. The proposed model is compared to experimental results.
Abstract
The shape of CdSe and other semiconductor nanocrystals is controlled, producing dots, rods, rice-shaped particles, tetrapods, or other elongated shapes. Monomer concentration in the growth solution is the determining factor in shape-control and shape-evolution. The elongated shapes could be transformed into more spherical shapes if the monomer concentration in the solution was lowered to a certain level, and spherically shaped nanocrystals could grow to elongated shapes by simply increasing the monomer concentration. The precursors are stable, inexpensive, and relatively non-toxic, and therefore good choices for the growth of nearly monodisperse and shape-controlled nanocrystals.