The Department of Applied Physics of Aalto University has, in co-operation with Canatu Oy, developed a simple, fast method to manufacture free-standing, multi-functional, single-walled carbon nanotube (SWCNT) films.
These SWCNT nanotubes are a remarkable family of materials exhibiting many diverse useful chemical and physical properties. These thin films, for example, have a great optical transmittance in relation to sheet resistance, high thermal conductivity and chemical sensitivity as well as adjustable conductance.
Usually carbon nanotube films are manufactured using the vacuum protection method which is a time-consuming and challenging process that can even have a negative impact on the properties of the tubes. The new production method solves many of these problems.
–With the method we have developed we can prepare SWCNT deposits both on different substrates and in the form of free-standing films (without a substrate) in less than 15 seconds. This is possible because we produce clean, crystallized, high quality carbon tubes directly in the gas from where they can be transferred to the thin films without additional separation or purification, explains David P. Brown, CEO of Canatu Oy.
The method easily allows Canatu to alter the thickness of multi-functional free-standing SWCNT films from a single layer (in the region of a nanometre) up to a few micrometres. The Finnish company is developing the commercial exploitation of SWCNTs.
Several Finnish universities participated in developing the new method, researching the films’ properties and the multi-functionality of the material. The free standing tubes can be used in very many applications.
−From the free-standing nanotube films we fabricated the world’s most efficient components for filtration of aerosol nanoparticles, transparent, flexible and highly conductive electrodes, extremely sensitive electrochemical sensors, laser absorbers, gas heaters, thermo acoustic loudspeakers and gas flow meters, says Professor Esko I. Kauppinen, of the research work.
The results of the research have been published in the journal ASC Nano: