Technology

• The most significant technological achievement of INFRA is a method of continuous production of extra-long carbon nanotubes. This method has been scaled-up and realized at a pilot site of INFRA Technology plc in the form of a pilot plant capable of producing CNT in big spools. Each spool accommodates up to 15 km of CNT. Out CNT are different not only due to extraordinary length, but also due to double-walled structure and hydrophilic surface. 
• This technology is unique at the moment, which affords possibilities for the development of novel composite and fibrous materials. - INFRA carbon nanotubes is a carbon nanostructured product produced by continuous float-catalysis method in the form of big spools. 
• The as-produced product is dominated by double-walled carbon nanotubes with significant admixtures of non-nanotube carbon, TWNT, MWNT and residual catalyst in the form of α-Fe and maghemite (usually 6-8 % wt). The DWNT are extremely long with length up to 80 mm. - 
• Purified INFRA nanotubes are available in the form of carbon felt and characterized by lower concentration of impurities, - in particular, Fe content drops down below 1.0 % wt. 
• INFRA nanotubes inks and dispersions are available in the form of opaque black liquid, where chopped nanotubes are dispersed in concentration 0.1 up to 2.0 % wt depending on a base liquid, which can be water or ethanol or acetone or N-DMP, etc.
• INFRA nanotubes paper is large-size paper-like material 100 to 200 µm thick prepared from dispersions by paper-like technology.
• Some technical solutions have already been developed and partly tested.

Other INFRA carbon nanotubes products (ultra-flexible CNT thread, CNT-doped cathode material for Li-ion battery, non-woven free-standing electrodes for supercapacitors, etc.) are available on request. All the INFRA nanotube products have been characterized by a number of experimental techniques. 

Some examples are shown below:

Examples: SEM showing fibrous nanostructure for purified CNT paper (on the left); and TEM showing DWNT structure for ultrasonically-dispersed CNT (on the right)