A First-Principles Study of Layered Materials for Low Friction Coating

Abstract Content

The development of environmentally sustainable, PFAS-free low-friction coatings is essential for improving the durability and tribological performance of engineering components. Polytetrafluoroethylene (PTFE), although widely used for its low coefficient of friction, suffers from environmental concerns, limited wear resistance, and performance variations across different contact surfaces. In this work, we combine first-principles calculations with experimental validation to investigate alternative coating materials for durable, non-fluorinated tribological applications.

Density functional theory (DFT) calculations are employed to examine heterostructures comprising a SiO₂ substrate, an Al₂O₃ interfacial layer, and two-dimensional materials including MoS₂, graphene, and hexagonal boron nitride (h-BN). The structural stability of the heterostructures is evaluated through binding energy calculations, while sliding energy barriers are used to predict frictional behaviour. The effect of interfacial oxygen on adhesion and sliding is also investigated to assess its influence on coating performance and durability.

Guided by the computational results, thin-film coatings are fabricated using atomic layer deposition (ALD) and evaluated experimentally through tribological testing to determine their coefficient of friction, wear behaviour, and durability. This integrated computational–experimental approach provides valuable insights into the design of next-generation PFAS-free low-friction coatings and establishes a framework for developing robust, environmentally friendly tribological materials for advanced engineering applications.