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Titania Nanotubes for Hydrogen Sensors?

Posted by Hemos on from the strong-and-stiff dept.

Roland Piquepaille writes "Everybody is talking about carbon nanotubes these days. But what about titania nanotubes? Penn State researchers think they have a great potential for sensing hydrogen . According to this news release, "titania nanotubes are 1500 times better than the next best material for sensing hydrogen and may be one of the first examples of materials properties changing dramatically when crossing the border between real world sizes and nanoscopic dimensions, according to a Penn State materials scientist." And now, the very good news: titania nanotubes are cheap. So they'll be used in industrial quality control in food plants and as weapons against terrorism. My summary contains some more details."

1 of 161 comments (clear)

  1. Re:cheap? by Goldsmith · · Score: 4, Interesting

    Well, I don't have a BS in Materials Science, but I'm working on a PhD in... well, lets call it nanoscience.

    I personally don't know how to make titanium oxide nanotubes, but I imagine it would be similar to making carbon nanotubes... which I do have experiance with.

    Allow me to show you...

    The way you make carbon nanotubes is simple. You start with a catalyst (everything from rust to specially tailored alloys has been used), place this catalyst on a clean substrate where you want the tube to start growing. Next, flow some carbon rich gas through a furnace (i.e. methane), add a little hydrogen. When hot, place your substrate in the furnace. Nanotubes will grow from the catalyst in the direction of the flow (mostly).

    That same method is used to grow many types of tubes and nanowires. The only hard thing is dealing with flammable and explosive gases at high temperature (I havn't blown anything up yet, but I'm trying), and keeping everything clean.

    When dealing with nanotubes, you have to remember that you want to get a specific shape out, and not amorphous material, and that can be very hard. In most cases, you tailor your catalyst to provide the general shape you want, and grow off of that. So you could very easily control the growth of a ceramic, but the shape?

    Now obviously, there are other ways to grow these things... but I'm going to stop now before this turns into a lecture.