Effect of Oxide Shell on Aluminium Nanoparticle Oxidation Using Molecular Dynamics Simulation

Abstract

Molecular dynamics simulation using reactive force field (ReaxFF)potential was implemented to study the oxidation mechanism in aluminium particles with two different alumina shells. That is, without an oxide shell and with a 1 nm oxide shell. In particular, this research investigated the atomic diffusivity of the system on the oxide shell effect. The results showed that in the heating process, oxygen molecules were adsorbed on the surface of the shell and then diffused to the particle core as the heating temperature increased. The diffusivity of oxygen molecules in the aluminium core which causes the oxidation process to occur, shows that the particles without the oxide shell are faster than the particles with the oxide shell. Although after relaxation, there are similarities in having an oxide shell. However, the thickness is different. This shows that the coating on Al particles can inhibit the rate of oxidation. The thickness of the oxide shell also affects the rate of oxidation.