Timing Matters: the Underappreciated Role of Temperature Ramp Rate for Shape Control and Reproducibility of Quantum Dot Synthesis
Baumgardner, William J.; Quan, Zewei; Fang, Jiye; Hanrath, Tobias
Understanding the coupled kinetic and thermodynamics factors governing colloidal nanocrystals nucleation and growth are critical factors in the predictable and reproducible synthesis of advanced nanomaterials. We show that the temporal temperature profile is decisive in tuning the particle shape from pseudo-spherical to monodisperse cubes. The shape of the nanocrystals was characterized by transmission electron microscopy and X-ray diffraction.We introduce a mechanism for the shape controlled synthesis in the context of temperature-dependent nucleation and growth and provide experimental evidence to support it.
The authors would like to thank Richard Robinson for helpful discussions. This publication was based on work supported by Award No. KUS-C1-018-02, made by King Abdullah University of Science and Technology (KAUST). We also acknowledge the Cornell Center for Materials Science (NSF DMR-0520404).
Royal Society of Chemistry
colloidal nanocrystals nucleation; quantum dot synthesis
Previously Published As
Nanoscale, 4, May 2012, 3625-3628