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Published on: July 8, 2016
Higher surface energy of free nanoparticles
K K Nanda1, A Maisels, F E Kruis
1Department of Electrical Engineering and Information Technology, University Duisburg-Essen, 47048 Duisburg, Germany. nanda@uni-duisburg.de
Physical Review Letters
|October 4, 2003
Summary
We developed a precise online method to track nanoparticle evaporation, detecting size changes as small as 0.1 nm. This study on silver nanoparticles confirms the Kelvin effect and reveals their high surface energy, crucial for nanoparticle behavior.
Area of Science:
- Nanotechnology
- Physical Chemistry
- Materials Science
Background:
- Understanding nanoparticle behavior is critical for various applications.
- The size-dependent properties of nanoparticles, such as evaporation, are not fully characterized.
- Surface energy plays a significant role in nanoparticle processes like melting and growth.
Purpose of the Study:
- To develop and apply an accurate online method for studying size-dependent evaporation of free nanoparticles.
- To investigate the evaporation of silver (Ag) nanoparticles.
- To determine the surface energy of free Ag nanoparticles and its relation to the Kelvin effect.
Main Methods:
- An accurate online measurement technique was employed.
- The method allowed for the detection of nanoparticle size changes as small as 0.1 nm.
- The technique was applied to study the evaporation of Ag nanoparticles.
Main Results:
- A linear relationship was observed between the onset temperature of evaporation and the inverse of the particle size.
- This relationship confirms the applicability of the Kelvin effect to free Ag nanoparticles.
- The surface energy of free Ag nanoparticles was predicted to be 7.2 J/m(2).
Conclusions:
- The surface energy of nanoparticles is significantly higher than that of the bulk material.
- The developed online method provides accurate insights into nanoparticle evaporation.
- The determined surface energy is essential for understanding and controlling nanoparticle processes such as melting, coalescence, and growth.
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