Dr. David Schoen, PhD, PE

Scientist develop new water filter

(21 Oct 2010) AP Television Stanford, California, recent 1. Close shot bottle of carbon nanotubes 2. Various David Schoen preparing water filter demonstration 3. SOUNDBITE (English) David Schoen, Postdoctoral Researcher in Materials Sciences, Stanford University: "We've been developing a technology that allows us to use a couple of simple inks in order to turn cotton into a high throughput bacteria filtering device." 4. Medium shot Schoen soaking cotton in carbon nanotube ink 5. Extreme close shot soaked cotton 6. Close shot Schoen 7. Close shot cotton in beaker 8. SOUNDBITE (English) David Schoen, Postdoctoral Researcher in Materials Sciences, Stanford University: "Other people in my lab had been trying to make cotton conductive for a variety of other purposes, for instance batteries and that kind of work. And so we had this idea a couple years ago that if we could somehow combine silver nanowires, which are fundamentally antibacterial in an intimate way with water, mix it at a very small scale, and then apply a voltage to the entire thing, we might be able to kill bacteria at an enhanced rate. The idea is very simple, we almost wanted to make a nanoscale bug zapper that would just be killing ecoli. 9. Close shot silver nanotubes 10. Schoen drips nanowires onto cottton with carbon on it already 11. Three types of filters - he opens dish with cotton coated only in silver 12. Filters with only silver nanowires 13. Zoom in filter with bacteria cultured on it, shows that bacteria avoids areas with silver 14. Various Stanford campus 15. Various signs for McCullough Building, Department of Materials Sciences 16. Yi Cui arriving on bicycle 17. Set up Yi Ciu 18. SOUNDBITE (English) Yi Cui, Associate Professor of Materials Science and Engineering, Stanford University: "It's very easy to use nanotubes to make the cotton conducting, the textile conducting, so we used nanotubes. And then silver came along because we wanted to use silver for another function. Silver intrinsically is antibacterial. So if you put silver nanowires into the filter, you don't need to do anything, and the bacteria cannot grow onto these filters. So eventually we have two functions. To make the filter conducting, and to make the filter antibacterial without even applying voltage." 19. Yi Cui drawing cotton fibre covered with carbon nanotubes on white board 20. Close shot Yi Cui drawing silver nanowires 21. SOUNDBITE (English) Yi Cui, Associate Professor of Materials Science and Engineering, Stanford University: "When we talk about low cost right here, of these filters, and it can certainly reach a potential low cost for the developing countries. I think the biggest savings come later - it's the amount of energy we use for water filtration, use our filters, it's much smaller than the existing filters, that's where you save a lot of money." 22. Close shot alligator clip with wire attached 23. Schoen connects wire to funnel where water will be poured 24. Schoen pours water into filter 25. Close shot water in funnel 26. Close shot funnel 27. Close shot water dripping 28. Extreme close shot water dripping LEAD IN: A team of researchers at Stanford University have found a way to purify water that they think will be faster and cheaper than existing methods. They're now looking at ways of turning the so called "nano-scale bug zapper" into a product that could be sold on a mass scale. STORYLINE: Here researcher David Schoen demonstrates how the filter is made. He fills the bottom of a test tube with carbon nanotubes mixed with water and a bit of detergent and dips a cotton square into the liquid. Find out more about AP Archive: http://www.aparchive.com/HowWeWork Twitter:   / ap_archive   Facebook:   / aparchives   ​​ Instagram:   / apnews   You can license this story through AP Archive: http://www.aparchive.com/metadata/you...

Massachusetts Institute of Technology

Bachelor of Science

Stanford University

Doctor of Philosophy

Stanford University

Master of Science

Principal Engineer

Exponent, Inc. (Menlo Park, CA)

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Stork MSC (Louisiville, KY)