Nanoparticle growth, coalescence, and phase change in the gas-phase by molecular dynamics

Gas-phase synthesis of nanomaterials offers distinct advantages in large-scale manufacturing of commodities such as carbon blacks, ceramic oxides, semiconductors, and dielectric substances and facilitates the formation of highly pure materials with unique morphology that impact transportation, microelectronics, catalysis, biomedicine, and energy applications. Particle characteristics such as size, morphology, composition, and crystallinity play a key role in the aerosol process design and operation optimization. Depending on process conditions and the growth mechanism, such nanostructured particles form aggregates which are used in catalysis, and electronics and/or agglomerates that are attractive in pigments, nanocomposites, and liquid suspensions. Molecular-based simulations have been used extensively over the past two decades to shed light into the early stages of particle growth and kinetics during dry synthesis. This article gives an overview of recent advances in molecular dynamics simulations for the investigation of particle nucleation, condensation and sintering or coalescence rates in the gas-phase highlighting the effect of particle characteristics, such as crystallinity, at the nanoscale, on end-product properties.