Graphene/molybdenum disulfide (MoS₂) heterostructure coatings are promising solid lubricants due to their intrinsic lattice mismatch and weak van der Waals (vdW) forces between chemically inert atomic layers. However, macroscale lubrication enhancement remains limited due to the competitive effect between in-plane edge interactions and incommensurability. Herein, graphene/MoS₂ heterostructure coatings with controlled heterogeneity are fabricated in situ by a magnetron sputtering method. The graphene/MoS₂ heterostructure coating outperforms its individual components in friction properties due to the synergistic integration of the chemical stability of graphene and the load-bearing capacity of MoS₂. Experiments and molecular dynamics (MD) simulations reveal that increased structural heterogeneity intensifies interfacial edge interactions, initially promoting structural disorder and frictional energy dissipation. Additionally, a load-driven self-passivation mechanism is uncovered to saturate dangling bonds and repair structural defects, consequently forming a robust passivated interface that facilitates smooth and well-ordered shear sliding. As a result of the synergistic interplay between load-driven edge self-passivation and structural heterogeneity, the highly heterogeneous graphene/MoS₂ coating exhibits a 3-fold friction reduction and 12-fold wear reduction under high-load conditions compared to low-load conditions. The results reveal a novel synergistic lubrication mechanism enabled by structural heterogeneity and load-driven interfacial engineering and offer insights into how to transform conventionally undesirable structural disorder into significant lubrication enhancements.

Pure Mg boasting a relatively small corrosion rate is a potential biodegradable metal material for implants. However, its degradation behavior in the complex physiological environment is still a lack of understanding. In this work, we investigated the effect of corrosion product film layers on the degradation behavior of pure Mg in physiological environments. Pure Mg shows a faster corrosion rate in simulated body fluid (SBF) compared to NaCl solution. Hydrogen evolution experiments indicate that the degradation rate of pure Mg in SBF decreases rapidly within the first 12 h but stabilizes afterward. The rapid deposition of low-solubility calcium phosphate on the pure Mg in SBF provides protection to the substrate, resulting in a gradual decrease in the degradation rates. Consequently, the corrosion product film of pure Mg formed in SBF exhibits a layered structure, with the upper layer consisting of dense Ca₃(PO₄)₂/Mg₃(PO₄)₂ and the lower layer consisting of Mg(OH)₂/MgO. Electrochemical impedance spectroscopy (EIS) shows that the resistance of the corrosion product film increases over time, indicating gradual strengthening of the corrosion resistance. The 4-week degradation results in the femoral marrow cavity of mice are consistent with the result in SBF in vitro.