The carbon nanofibers.
Carbon nanofibers (carbon nanofibers) are threadlike particles, built from a very large number of graphene layers stacked at a certain angle relative to the axis of the fiber.
Carbon nanofibers (carbon nanofibers) represent filamentous particles, built from a very large number of graphene layers stacked at a certain angle relative to the axis of the fiber. The diameter of the fibers varies in a wide range, reaching in some cases 200 nm.
Form graphene layers of the carbon nanofibers may be different from the actual plane and plates to the folded sheet in the form of cones, cups, etc. the Distance between graphene layers in the carbon nanofibers is similar to the distance between graphene layers in graphite is 0.34 nm.
Carbon nanofibers are one of the allotropic forms of carbon , alongside diamond, graphite, graphene, carbon nanotubes, fullerene, carbyne , etc.
Get carbon nanofibers by chemical vapor deposition (CVD) in different ways.
The internal structure of carbon nanofibers is represented by the following types: “stacked coins”, “tree” (a stack of cones), the “stack of cups” (“lamp shades”), “Russian doll”, “bamboo”, nanofiber with spherical sections, nanofibers with polyhedral partitions and the “fish spine”. She is the internal structure of the carbon nanofibers can be characterized by the angle α between the graphene layers and the axis of the fiber (filament). In the case of these carbon nanotubes, the angle α is equal to zero.
The diameter of the nanofibers and their internal structure determined by the characteristics of the synthesis process, including the form of catalytic particles and the composition of the catalyst, temperature of synthesis, composition and flow rates of the gas mixture, etc.
Carbon nanofibers possess unique thermal, electricalshielding and mechanical properties, which in turn determines internal structure of nanofibers. Due to its unique properties and low cost carbon nanofibers are increasingly being used as additives in various materials, such as composites.
Benefits and properties of carbon nanofibers:
– possess high mechanical and strength characteristics (young’s modulus, tensile strength). This means that they are able to play the role of a reinforcing element in various composite materials
– carbon nanofibers constructed from graphene planes. Graphene plane, moreover, constitute the core of the particles of technical carbon, one of the main fillers of rubber,
– possess the ability to reversibly deform under the action of different types of loads without failure, including during uniaxial tension, repeated cyclic loads,
– have electrical and thermal conductivity.
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