Roland Piquepaille writes "Carbon nanotubes, which can have useful electrical or optical properties, are typically grown using chemical vapor deposition techniques. During this process, amorphous and useless carbon layers are also produced, meaning that a post-growth purification process is needed. Not anymore. According to this article from Technology Research News (TRN), Japanese researchers have successfully used water to get rid of these impurities. The idea of using water to clean carbon nanotubes is so simple that I'm amazed that nobody thought about it before. Anyway, this method, which eliminates the post-growth purification process, still needs some improvements and will not help to mass produce carbon nanotubes before at least five years. You'll find more details and references in this overview. And you'll find even more nanotechnology achievements in this Nanotech News Roundup #1."