Solute Concentrations and Strains in Nanoparticles

Abstract

The Gibbs-approach based adsorption isotherm is applied to surface segregation in nanoparticles. A nanoparticle is treated to be as a composite with a core lattice and a surface shell and both core and shell possess their thermodynamic properties. The Gibbs-approach based adsorption isotherm has the ability to analyze simultaneously stresses, concentrations and their coupling behaviors in the surface shell and the core lattice. The thermodynamic analysis shows that the apparent solute concentration could be greatly enhanced in nanoparticles, due to a large surface volume fraction and a considerable increase in the lattice concentration that is, in turn, boosted by the concentration-induced stresses.

Keywords:

• Coupling between stress and concentration
• Nanoparticles
• Surface segregation
• Stresses
• Solute concentrations

Acknowledgments

The work was supported by the Hong Kong Research Grants Council through research grant N_HKUST621/11 under the NSFC/RGC Joint Research Scheme and by the Engineering School, Hong Kong University of Science and Technology (HKUST), through the Distinguished Research Excellence Award grant, SBI12EG01. H Ren was partially supported by the Nanotechnology Program at HKUST.