Molecular dynamics simulation of the melting processes of core–shell and pure nanoparticles

Abstract

Core–shell nanoparticles are nanosized particles that consist of a core and a shell, constructed from different metallic elements. Core–shell nanoparticles have received extensive attention, owing to their various potential applications such as paints, optical films and catalysts. Herein, we investigate the melting behaviours of different core–shell nanoparticles under continuous heating using molecular dynamics simulation. Different metallic elements were examined as core–shell and pure nanoparticles. Five different processes were observed during the melting of core–shell nanoparticles. In contrast, only one process was identified during the melting of pure nanoparticles. These processes were influenced by the nanoparticle size, shell thickness and differences between the lattice constants and melting point temperatures of the metallic elements. Our simulation provides microscopic insights into the melting behaviours of existing and proposed core–shell nanoparticles that would be highly beneficial towards the fabrication of materials with different chemical coatings.

Keywords::

• core–shell nanoparticle
• molecular dynamics
• phase transition
• melting process

Acknowledgements

N.A. was supported by the JSPS KAKENHI Grant number 25870229 and in part by a grant of the Strategic Research Foundation Grant-aided Project for Private Universities from the Ministry of Education, Culture, Sport, Science, and Technology, Japan (MEXT), 2012–2014.