To remove iron left over from the manufacturing process, the nanotubes are placed in a chamber above a flask of boiling hydrochloric acid. Evaporated acid precipitates in the upper chamber and drips over the nanotubes and back into the flask below, carrying the iron with it.
Katherine BourzacI’m a freelance journalist based in San Francisco, California, and a contributing editor at MIT Technology Review, where I was previously on staff as materials science editor. I write about materials science, computing, and medicine. My favorite nanomaterial is carbon nanotubes and my favorite quasiparticle is the plasmon. I serve on the board of the Northern California chapter of the Society of Professional Journalists. I graduated from MIT’s science writing program in 2004.