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Flash NanoPrecipitation for the Encapsulation of Hydrophobic and Hydrophilic Compounds in Polymeric Nanoparticles
Published on: January 7, 2019
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Out-of-Equilibrium Polymorph Selection in Nanoparticle Freezing.
Jonathan Amodeo1, Fabio Pietrucci2, Julien Lam3
1Université de Lyon, INSA-Lyon, MATEIS, UMR 5510 CNRS, 69621 Villeurbanne, France.
The Journal of Physical Chemistry Letters
|September 4, 2020
Summary
Designing out-of-equilibrium synthesis allows for novel nanomaterials. Controlling cooling rates during nanoparticle freezing enables selection of specific atomic structures, like metastable Ni3Al, for advanced applications.
Area of Science:
- Materials Science
- Nanotechnology
- Computational Chemistry
Background:
- Out-of-equilibrium synthesis offers access to unique nanomaterials with tunable properties.
- Controlling atomic arrangements is crucial for advanced material functionalities.
Purpose of the Study:
- To demonstrate control over polymorph selection in nanoparticles using cooling rates.
- To rationalize the nucleation process and identify pathways to metastable states.
Main Methods:
- Atomistic simulations were employed to model nanoparticle freezing.
- State-of-the-art free-energy calculations were used to analyze nucleation pathways.
Main Results:
- Cooling rate during nanoparticle freezing dictates the selected polymorph of Ni3Al.
- Two distinct kinetic pathways were identified, leading to equilibrium and metastable structures.
- A switch between kinetic pathways was discovered based on cooling rate.
Conclusions:
- Rational design of nanomaterial synthesis can exploit kinetics versus thermodynamics.
- Controlling treatment history enables the formation of desirable metastable states in nanoalloys.
- This approach facilitates the creation of advanced nanoalloys for technological applications.
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