Formation of MoS2 from elemental Mo and S using reactive molecular dynamics simulations

Mo- and S-based lubricant additives reduce friction in boundary lubrication through the formation of molybdenum disulfide ( MoS 2) during operation. However, the fundamental mechanisms of MoS 2 formation are still not fully understood, in part because direct experimental measurement is challenging during the crystallization process. Previously, reactive molecular dynamics simulations were used to model the formation of crystalline MoS 2 by compressing and heating amorphous material consisting of Mo and S. Here, the authors test the robustness of these models to capture the crystallization process under different simulation conditions and with different reactive force fields. Lastly, a reactive force field that contains parameters for Mo, S, and O was modified to enable it to capture MoS 2 crystallization in the presence of oxygen.