Long-term wear characteristics of single-layer h-BN, MoS₂, and graphene

Two-dimensional (2D) materials such as hexagonal boron nitride (h-BN), molybdenum disulfide (MoS₂), and graphene have attracted attention as surface-protective coatings and lubricants. This study investigates the long-term tribological characteristics of single layer h-BN, MoS₂, and graphene using atomic force microscopy and molecular dynamics simulations. Wear tests were performed with colloidal probes under micronewton-scale loads for up to one million cycles. All 2D materials demonstrated remarkably low friction before failure. MoS₂ and graphene exhibited exceptionally low wear rates (∼1 μm³/N∙m), among the lowest reported at the nanoscale. In contrast, h-BN failed prematurely due to concentrated atomic stress and weak substrate adhesion. Wrinkle formation also significantly reduced wear resistance. These findings provide insights and a framework for tribological design using 2D materials.