Molecular dynamics computation of gas-phase nanoparticle sintering: a comparison with phenomenological models

The mechanism and kinetics of the growth of silicon nanoparticles via particle–particle interactions has been investigated through the use of classical molecular dynamics (MD) trajectory calculations. Computations over a broad range of temperatures and particle sizes have shown that particle sintering is very dependent on size and temperature when solid-like, and considerably less sensitive when liquid-like. These atomistic computations have been used for the first time to validate previously postulated phenomenological mechanisms/models for both solid and liquid particle coalescence. The results have shown that solid-like particles sinter by a solid-state diffusion mechanism while liquid-like particles sinter by a viscous flow mechanism.