Improved wettability of carbon nanotubes opens the door to new possibilities

Carbon nanotubes have long been touted as the wonder material of the future but their wonder properties can also be their downfall. The non reactive nature of carbon nanotubes means they can be difficult to incorporate into other materials for real world applications.

To this end, researchers have now extensively studied the wettability of carbon nanotubes in the form of powder, grown on a Si substrate and as CNT sheets or mats, or bucky paper.

The international research team of Uwe Vohrer, Justin Holmes, Zhonglai Li, AunShih Teh, Pagona Papakonstantinou, Manuel Ruether and Werner Blau, published their work in a special edition of the open access journal, AZoJono. This special edition of AZoJono* features a number of papers from DESYGN-IT, the project seeking to secure Europe as the international scientific leader in the design, synthesis, growth, characterisation and application of nanotubes, nanowires and nanotube arrays for industrial technology.

The researchers found that plasma polymerisation of a carbofluorine monomer onto a bucky paper leads to superhydrophobic surfaces. They also found that under gentle oxidation parameters the vertical alignment of multi wall nanotubes remains unchanged whereas more harsh conditions destroy the carbon nanotube shape without opening the end caps.

However, the most important finding was that when the carbon nanotube bucky papers were processed using a plasma treatment utilising oxygen containing process gases or post treatment reaction with oxygen after plasma activation they were able to convert the surface from hydrophobic to hydrophilic. Suitable treatments resulted in instant wetting and contact angles of less than 10° which could pave the way for carbon nanotube incorporation into many new applications as well as improved properties for those materials and application that already involve carbon nanotubes.

The complete article is available to view in AZoJono at http://www.azonano.com/Details.asp?ArticleID=2042.