Large‐Area Atomically Thin WS ₂ Enables Exceptionally Scratch‐Resistant Silica Glass

Abstract Beyond aesthetics, scratch damage on glass surfaces significantly affects their mechanical strength and other critical functionalities. Here, it is demonstrated that the large‐scale growth of atomically thin WS ₂ films on silica glass via chemical vapor deposition can result in ultra‐scratch‐resistant surfaces. Through rigorous scratch tests using atomic force microscopy, it is observed that even a monolayer of WS ₂ can subdue nanoscale friction by ≈95%, effectively averting severe plowing wear. Instead, minor distortions of the glass surface are recorded owing to the combined load‐bearing and low‐shear WS ₂ monolayer. To elucidate the mechanism behind the exceptional scratch resistance, atomistic simulations are employed, which reveal that while WS ₂ evidently shields the normal stresses during indentation, nominal shear stresses eventually act on the glass during scratching. Consequently, shear‐induced bond‐breaking and bond‐switching transitions are observed in the contact subsurface that prematurely densify the silica network as a non‐wear dissipating mechanism. Altogether, the present study showcases the potential of two‐dimensional WS ₂ coatings for new‐generation scratch‐resistant glass and provides fresh perspectives into their protection mechanisms.