Spontaneous Nanocrystals/Amorphous MoS₂ Film Induced by Fe⁺ Irradiation with Superior Irradiation Tolerance and Tribology Properties

High-performance radiation-resistant lubricating materials (RRLMs) with nanostructures hold great promise for enhancing the irradiation tolerance because of their sinking effect of boundaries on defects. Despite recent advances, challenges remain in finding a nanostructure that exhibits both superior irradiation tolerance and excellent lubricant properties. Unlike traditional nanostructured composite materials that required complex predesign, herein, a MoS₂ nanocrystals (NCs)/amorphous dual phase in subirradiation saturation (SIS) state was spontaneously formed during irradiation, exhibiting high irradiation resistance under the synergistic effect of "defect traps" by interfaces and edge dislocation. This nanocrystals (NCs)/amorphous dual phase where each has its own advantages exhibits a significant reduction in both friction coefficient and wear rate even under irradiation damage of 8 dpa, pushing the limit of irradiation performance for current solid lubricants. Furthermore, based on the molecular dynamics (MD) analysis, other factors influencing the intrinsic irradiation tolerance of MoS₂, such as collision angles and S off-sites, have also been comprehensively investigated to clarify the damage mechanism of MoS₂. Our findings offer advanced perspectives for the design of high-performance RRLMs, enabled by edge dislocations, S off sites, and crystal orientation, inspiring the fabrication of structural-functional integrated materials in extreme environment applications such as nuclear reactors.