Carbon Nanomaterials
Carbon Nanotubes (CNT) and Carbon Nanofibers (CNF)
FutureCarbon manufactures and produces a wide range of carbon nanomaterials. The class of carbon nanomaterials can be further subdivided into the class of carbon nanotubes (CNT) and that of carbon nanofibers (CNF). The main difference between carbon nanotubes and carbon nanofibers lies in the configuration of the underlying planes that are created by the alignment of carbon atoms. While nanotubes display an axial alignment of concentric cylindrical planes mainly composed of hexagonal substructures, nanofibers are characterized by a parallel and homogeneous alignment of nanoscopic graphene layers along the axis.
The material-specific properties defined by the morphology enable technological leaps for novel applications and even for existing ones. This innovative power is due to the novelty of the basic materials or to factors such as the improved workability resulting from the small quantities of nanomaterials needed in order to assure the desired functionality.Properties of carbon nanotubes
Carbon nanotubes are cylindrical tubes of nanoscopic dimensions. There are two types of nanotubes: CNT-SW (single-walled nanotubes) and CNT-MW (multi-walled nanotubes). Typical diameters range from a few nanometers (approx. 5 - 30nm, and even <1nm for single-walled nanotubes); typical lengths are in the range of a few millimeters.
The substructure of carbon nanotubes (“armchair”, “zigzag”) is derived from the type of process used during synthesis, and affects features such as the existence of semiconductor properties. The electric and thermal properties of the raw materials are greatly superior to those of conventional materials. In particular, correct insertion of the carbon nanotubes into a material matrix will cause a significant shift of the percolation curve towards reduced material concentrations. These promising properties are based on the emergence of a network that takes advantage of the high aspect ratio between the length and the diameter. The formation of networks also supports the improvement of mechanical properties within the matrices, particularly as the basic material has a tensile strength (11 - 63GPa) 20 times that of steel.
Properties of carbon nanofibers
FutureCarbon currently produces two different types of carbon nanofibers, platelets (CNF-HB) and herringbones (CNF-HB), which are created by varying the alignment of parallel nanoscopic graphene layers with homogeneous interstices. Like carbon nanotubes, they have a high aspect ratio with typical diameters ranging from 150 to 300 nm depending on the type. Listed below are some of the fields of application in which the specific morphology of the materials is utilized:
- The multiple corners and edges can be utilized for the highly efficient and stabilized support of catalyst particles in heterogeneous and enzymatical catalysis. Such catalysts feature great selectivity in the material conversion process and can withstand many cycles without degradation.
- Metallic intermediate layers applied in a similar manner allow the carbon networks to be better linked with the matrices of ceramic or metallic composite materials. These layers thus combine the desired physical properties of these material classes.
- The homogeneous stacking of the graphene layers opens up further fields of application which make use of the sliding of single graphene layers for constant self-lubrication of composites.
