Molecular Dynamics Simulations of Nanocutting Mechanism on Black Phosphorus Layers: Implications for Chemical Sensing

Black phosphorus (BP) stands out among vdW materials for chemical sensing, with its edge sites offering the potential to enhance performance. While the nanocutting method shows promise for BP edge fabrication, the underlying mechanism remains unclear, lacking guidance for the process. In this study, molecular dynamics (MD) simulations were conducted to investigate the material removal behavior during nanocutting of BP while considering the influence of cutting thickness, tool edge radius, and tool angle. These findings indicate that the plastic removal of BP is primarily governed by interlayer slip when using a cutting tool with a relatively large rake angle. In contrast, at a small rake angle, a brittle removal state occurs due to the formation and expansion of a shear band spanning across the BP layers, leading to crack propagation. Additionally, as the cutting thickness approaches the tool edge radius, a “size effect” is observed in the BP. This phenomenon results in both decreased plastic deformation and a singular decrease in cutting force, ultimately causing an increase in chip thickness deviation. The research findings offer a comprehensive theoretical foundation for the removal behavior of BP and serve as a technical reference for the fabrication of nanostructures for chemical sensing via nanocutting.