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Synthesis of Bimetallic Pt/Sn-based Nanoparticles in Ionic Liquids
Published on: August 23, 2018
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Solvent Effects in Ligand Stripping Behavior of Colloidal Nanoparticles
Akhlak U Mahmood1, Mehedi H Rizvi1, Joseph B Tracy1
1Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States.
ACS Nano
|June 13, 2023
Summary
Controlling nanoparticle properties involves ligand stripping. This study reveals ethanol concentration thresholds and hydrogen bonding effects on ligand stripping from magnetite nanoparticles, validated by simulations and experiments.
Area of Science:
- Materials Science
- Nanotechnology
- Physical Chemistry
Background:
- Colloidal nanoparticle properties are tunable via ligand stripping.
- The nanoscale mechanism of ligand stripping is poorly understood due to measurement challenges.
Purpose of the Study:
- Investigate ethanol-mediated oleylamine ligand stripping from magnetite (Fe3O4) nanoparticles.
- Elucidate the role of solvent composition and interactions in ligand stripping.
Main Methods:
- Atomistic molecular dynamics (MD) simulations.
- Thermogravimetric analysis (TGA).
- Investigated ethanol/hexane mixtures.
Main Results:
- Identified a threshold ethanol concentration (~34 vol %) for ligand stripping saturation.
- Demonstrated that hydrogen bonding between ethanol and ligands inhibits readsorption.
- Developed a modified Langmuir isotherm to explain ligand stripping mechanisms.
Conclusions:
- Ligand coverage on nanoparticles can be controlled using poor solvents below a threshold concentration.
- Ligand-solvent interactions significantly modulate colloidal nanoparticle properties.
- The study offers an in silico approach for studying ligand stripping crucial for NP applications.
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