Molecular Dynamics Study of Nanoparticle Collision with a Surface-Implication to Nanoparticle Filtration

Shintaro Sato ； Da-Ren Chen ； David Y. H. Pui

《Aerosol and Air Quality Research》 7卷3期 (2007/09) Pp. 278-303

並列摘要

Collision dynamics of nanoparticles with a surface was studied by classical molecular dynamics simulations. Silver, nickel and silica were selected as the particle materials, and silver as the surface material. Particle sizes ranged approximately from 0.5 to 2 nm. The results indicate that particles with thermal energy at room temperature do not bounce off a surface, even when a very weak interaction potential between the particles and the surface is assumed. The loss mechanisms of the center-of-mass energy of nanoparticles colliding with a surface were also investigated. The findings indicate that energy losses to the surface and the rotational degree of freedom are important. The loss to the surface is significant when a harder particle hits a softer surface. This is because the center-of-mass energy is mainly transferred to the surface as elastic energy, and the energy is not effectively transferred back to the particle. Non-spherical silica particles were found to lose more energy than the other types of particles. This phenomenon is due to a large energy transfer to the rotational degree of the freedom upon collision.

並列關鍵字

Molecular dynamics ； Nanoparticle collision ； Nanoparticle filtration