Select your localized edition:

Close ×

More Ways to Connect

Discover one of our 28 local entrepreneurial communities »

Be the first to know as we launch in new countries and markets around the globe.

Interested in bringing MIT Technology Review to your local market?

MIT Technology ReviewMIT Technology Review - logo

 

Unsupported browser: Your browser does not meet modern web standards. See how it scores »

Cui isn’t sure just how the filter works, but he knows the two materials are better together. Silver has long been known to have antimicrobial properties, and carbon nanotubes are highly conductive. One guess is that very strong local electrical fields are formed at the tip of the silver nanowires, piercing the cell walls. When the electricity is off, the silver prevents bacteria from fouling the surface, a common problem with filters.

There have been no definitive studies of the effects of water-borne carbon nanotubes and silver nanowires on people and lower organisms; experiments with airborne carbon nanotubes have shown that their effect on mice lungs is similar to the effect of asbestos. But early tests on thousands of gallons of water suggest that the nanomaterials are not leaching into the water. The researchers will perform further tests to determine whether the nanomaterials remain enmeshed in the filter or are dislodged into the water over time.

“I believe there is tremendous potential for technological breakthroughs such as this to dramatically improve the options for low-cost water treatment,” says Kara Nelson, professor of civil and environmental engineering at the University of California, Berkeley. Now it’s important to take this proof-of-concept device to the next step, says Nelson, by improving the filter’s efficacy and demonstrating that it can work with a broad range of water-borne pathogens, including viruses and protozoa.

Chad Vecitis, professor of environmental engineering at Harvard University, says the most impressive aspect of the filter is its speed. Many university researchers are addressing the clean-water problem, but other low-power solutions take too long or are too complex. For example, some systems use a light-activated catalyst to kill bacteria in clear containers of water that are set out in the sun. This takes several hours, and it’s not easy to tell when the sterilization is done.

Gain the insight you need on energy at EmTech MIT.

Register today

10 comments. Share your thoughts »

Credit: Technology Review
Video by Katherine Bourzac, edited by Brittany Sauser

Tagged: Computing, Materials, energy, carbon nanotubes, water, materials science, water filtration, water treatment

Reprints and Permissions | Send feedback to the editor

From the Archives

Close

Introducing MIT Technology Review Insider.

Already a Magazine subscriber?

You're automatically an Insider. It's easy to activate or upgrade your account.

Activate Your Account

Become an Insider

It's the new way to subscribe. Get even more of the tech news, research, and discoveries you crave.

Sign Up

Learn More

Find out why MIT Technology Review Insider is for you and explore your options.

Show Me
×

A Place of Inspiration

Understand the technologies that are changing business and driving the new global economy.

September 23-25, 2014
Register »