The mechanical exfoliation mechanism of black phosphorus to phosphorene: A first-principles study
Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University Lanzhou 730000, China
Received: 15 September 2015
Accepted: 29 October 2015
Today, the renaissance of black phosphorus largely depends on the mechanical exfoliation method, which is accessible to produce few-layer forms from the bulk counterpart. However, the deep understanding of the exfoliation mechanism is missing. To this end, we resolve this issue by simulating the sliding processes of bilayer phosphorene based on first-principles calculations. It is found that the interlayer Coulomb interactions dictate the optimal sliding pathway, leading to the minimal energy barrier as low as , which gives a comparable surface energy of in experiment. This means that black phosphorus can be exfoliated by the sliding approach. In addition, considerable bandgap modulations along these sliding pathways are obtained. The study like ours builds up a fundamental understanding of how black phosphorus is exfoliated to few-layer forms, providing a good guide to experimental research.
PACS: 73.22.-f – Electronic structure of nanoscale materials and related systems / 68.65.-k – Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties / 68.35.-p – Solid surfaces and solid-solid interfaces: structure and energetics
© EPLA, 2015