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Updated: May 25, 2026
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Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles
Published on: June 25, 2018
Predicting nanocrystal shape through consideration of surface-ligand interactions
Clive R Bealing1, William J Baumgardner, Joshua J Choi
1Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA. crb242@cornell.edu
ACS Nano
|February 15, 2012
Summary
Ligand coverage on lead selenide (PbSe) nanocrystals influences their shape. Increasing oleic acid concentration alters PbSe nanocrystal equilibrium shape from octahedral to cubic.
Area of Science:
- Materials Science
- Nanotechnology
- Computational Chemistry
Background:
- Lead selenide (PbSe) nanocrystals are crucial in optoelectronics.
- Surface ligands control nanocrystal properties and shape.
- Oleic acid is a common ligand for PbSe synthesis.
Purpose of the Study:
- To investigate the binding energies of oleic acid-based ligands on PbSe facets.
- To determine how ligand coverage affects PbSe nanocrystal surface energies.
- To predict the equilibrium shape of PbSe nanocrystals as a function of ligand concentration.
Main Methods:
- Density functional calculations were employed to compute binding energies.
- Surface energies were analyzed as a function of ligand coverage.
- Wulff construction was used to predict equilibrium nanocrystal shapes.
Main Results:
- Oleic acid binds to PbSe surfaces as lead oleate.
- Differential binding energies on {100} and {111} facets were observed.
- A transition from octahedral to cubic shape is predicted with increasing ligand concentration.
Conclusions:
- Ligand surface coverage is a key factor in controlling PbSe nanocrystal morphology.
- Synthesis conditions, specifically oleic acid concentration, can tune nanocrystal shape.
- Understanding ligand-surface interactions is vital for designing PbSe nanocrystals with desired properties.
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