Carbon nanotubes (CNTs)
Carbon nanotubes (CNTs) feature a cylindrical nanostructure of one or more layers of graphene single-walled(denoted (SWNT) or multi-walled (MWNT) nanotubes). CNTs exhibit various remarkable structural and electronic properties and are highly valuable for potential applications in e. g. molecular electronics, optics as well as many other fields of materials science (see below).
Individual SWNTs are excellent heat conductors (3500 - 4000 W/(m·K)) and exceed even the thermal conductivity of diamond (2300 W/(m·K)). The graphene framework enables an outstanding electric conductivity and a huge current carrying capacity (109 A/cm2) 1000 times higher than copper. In addition CNTs can be actually transformed from metal like compounds to large-gap semiconductors depending on the winding of hexagons along the tube. Incorporation of even as low as 0.01 weight percent of carbon nanotubes enables conductivity in plastics.
A further compelling characteristic of CNTs is the exceptional tensile strength which provides in case of SWNTs an over 100 times higher tensile strength than steel. Associated with the comparable low densities of 1.3-1.4 g/cm3 CNTs are predestinated for applications as light but highly enduring composite materials.
Various commercial applications of CNTs were already realized due to their unique properties. CNTs are incorporated e.g. in new composite materials (bicycle components, surfboards, wind turbines), in transparent conductors (as alternative for ITO) and as promising channel materials in field-effect transistors (FETs). Furthermore, they are investigated as potential sensors, coatings or electrode materials for batteries and explored regarding their potential for gas (mostly H2) and energy storage. The increasing number of publications and patents as well as the raised annual production capacity demonstrates the great interest in this field of research and the high expectations in terms of CNTs product implementation.
IOLITECNanomaterials offers a wide range of different carbon nanotubes with high purities (90-95+%) for applications in laboratory or pilot plant areas. Our reasonable priced selection covers single-, double-, as well as multi-walled CNTs with diameters from 1 to 100 nm and lengths of 1-20 μm. Standard sizes (5-100 g) are in stock and can be delivered within very short times. For special applications we also provide functionalized CNTs (-OH, -NH2, -COOH).
For most applications a long term stable and easy-to-handle dispersion is highly desirable. Therefore IoLiTec developed a method to disperse MWNT (concentrations up to 10%) in water based solutions by using suitable ionic liquids. Please have also a look at our novel products, which have already been used successfully for inkjet printing to obtain conductive layers on paper.
Text: IOLITEC GmbH, 2013.