Analysis of MoS2 and WS2 nano-layers role on the radiation resistance of various Cu/MS2/Cu and Cu/MS2@Cu@MS2/Cu nanocomposites

Abstract

Nanocomposites with 2D materials are promising systems in extreme radiation environments and space technologies due to their superior combination properties. A wide range of research has been performed in the application of nanocomposites for controlling radiation-induced damages in material exposed to extreme radiation environments. The collision cascades induced by 6 keV primary knocked-on atoms (PKAs) in Cu/MS2/Cu and Cu/MS2@Cu@MS2/Cu nanocomposite are studied using classical molecular dynamics (MD) simulations. Results show that the number of residual point defects in bulk region of Cu-MS2 nanocomposites is always less than that of pure copper. The results imply that the composite resulting from Cu-MS2 interfaces exhibits extraordinary ability to resist radiation damage. The higher thermal conductivity of MoS2 can enhance the thermal conductivity of nanocomposites and the interface interception effects. Consequently, the number of residual defects in the cascade bulk (bulkc) region decreases. The irradiation-induced displaced sulfur and molybdenum atoms of the MoS2 layers can't get rid of bonds. This phenomenon highlights the role of the Mo-Mo, Mo-S, and S-S bonds to inhibit the defects in the sub-cascade bulk (bulksc) region. However, increasing copper nanocomposites’ radiation resistance by using MoS2 layers as the nearest plane to the bulkc and bulksc regions can suggest a new model with 2D materials to design generation IV reactors and the infrastructures of spacecraft systems.