Robust high-performance self-lubrication of nanostructured Mo-S-Cu-B film

Molybdenum disulfide (MoS2) has long been used as a superb lubricant in aerospace applications, but attempts to extend its use in more diverse environments have met great challenges of deteriorating performances caused by oxidation effects in terrestrial air and short service lifetime due to weak mechanical strength. Here, we present a new pathway for developing MoS2-based robust high-performance self-lubrication with concurrent ultralow friction and wear in both nitrogen and humid air environments achieved in nanostructured Mo-S-Cu-B film. In this tailor-designed nanostructure, boron passivates oxidation sites and strengthens film via densification, while copper induces the formation of curved MoS2 (002) nanosheets to provide an abundant lubricant source. The present method of optimizing tribological properties via rational multicomponent nanostructure design may help develop a distinct class of superb self-lubricating films.