Modeling of fishbone-type carbon nanofibers: A theoretical study

Five models for fishbone-type carbon nanofibers (f-CNFs) have been proposed and their geometries have been optimized through molecular dynamics and molecular mechanics simulations. The angle between graphene layers and fiber axis can take the values 9.71°, 19.60°, 30.03°, 41.99°, and 56.43°, which agree satisfactorily with the experimentally determined values. With reduction of the angle, the interlayer spacing of graphene sheets increases from 0.3376 nm to 0.3392 nm accordingly, due to the strain of the graphitic cones. In addition, X-ray diffraction (XRD) simulations are also implemented. With the high-resolution transmission electron microscopy (HRTEM) results taken into account, the XRD simulations verify that f-CNFs can adopt not only a regular arrangement but also a turbostratic way, and our models are good approximations for describing the bulk microstructures of f-CNFs.