Winding a nanotube from black phosphorus nanoribbon onto a CNT at low temperature: A molecular dynamics study

Black phosphorus (BP) has become a popular two dimensional semiconducting material. Investigation of a BP nanotube, theoretically and experimentally, is therefore a hot topic attracting many recent researchers. In this paper, a nanotube system is proposed by placing a BP ribbon near a carbon nanotube (CNT) to form a BP nanotube. The system is formed based on the following two aspects. The first is that the CNT has a perfect surface that provides only van der Waals attraction to the BP ribbon. The BP ribbon does not damage the CNT. The second aspect is that a BP ribbon can feature a large curvature without breaks of the phosphorus-phosphorus bonds in it. If the length of the BP ribbon is well chosen to be a ‘perfect length’, the ribbon can form a perfect BP nanotube winding on a CNT at very low temperature. At higher temperature, e.g., ≥ 50 K, it is difficult to obtain a perfect BP nanotube. With a BP ribbon whose length is greater than the perfect length, it is difficult to create a perfect BP nanotube even at ultralow temperature.