Molecular dynamics simulations of growth and properties of FeCl2–NaCl-nanoparticles in supercritical water

Abstract

Nanoparticle formation in supercritical water containing Fe²⁺, Na⁺, and Cl⁻ ions at different state points between temperatures of 798 K and 873 K and system densities of 0.24 g cm⁻³ and 0.14 g cm⁻³ has been studied by molecular dynamics simulations. A fixed amount of FeCl₂ and different amounts of NaCl content have been used to study the effect of system composition on particle growth and the time development of particle composition from single ions dissolved in aqueous solutions. Certain stable cluster sizes are observed during the particle growth. The salt particle structure at the end of the simulation runs is described by means of radial distribution functions. We find that clusters with disordered crystal structure form during the very fast formation and growth process. As the clusters grow very fast, the growth proceeds via non-equilibrium cluster structures.