Molecular dynamics simulations of aluminum nanoparticles adsorbed by ethanol molecules using the ReaxFF reactive force field

The adsorption of ethanol molecules on annealed aluminum nanoparticles was investigated by ReaxFF molecular dynamics simulations. The force field used in this paper has been validated by comparing the obtained adsorption process results with the results of quantum mechanical (QM) calculations. First, the case of single molecule adsorption was investigated and was shown to be a kind of chemisorption. We also simulated the processes of coating the aluminum nanoparticles with ethanol molecules at different temperatures and pressures. The results indicate that two zones were formed around the surface of aluminum nanoparticles by different interactions during the adsorption processes. The radial distribution function plots and isothermal adsorption curves were used to describe the behaviors. The results show that hydrogen-bonding formed by the ethanol molecules in the solution is a constituent of the coating layer and that the adsorption rate is proportional to the pressure. The cycle-coating method is adopted to produce a fully coated particle, and the oxidation resistance test shows that at 300 K, the organic layer can adsorb the oxygen atom rather than decompose by oxidation. Our simulation results are in good agreement with the results of experimental observations.