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 »

{ action.text }

In addition to reducing costs by using less active material, LaPierre’s team can also cut the cost of the substrate that the nanowires are grown on. LaPierre’s team doesn’t require an expensive Group III-V substrate. It has successfully grown its nanowires on substrates made of more plentiful and relatively cheaper silicon. It’s also working on using even lower cost substrates made of glass, which would be ideal for building-integrated PV applications. Flexible substrates such as polymer films and carbon nanotube fabric could be useful for many applications, and could be manufactured with inexpensive roll-to-roll processes.

To further drive down costs, the focus on cheaper substrates will be complemented by an attempt to replace the gold catalysts used to grow the nanowires with aluminum, although more work in this area is needed to achieve the necessary nanowire densities. “We have grown nanowires from aluminum, but gold works much better,” says LaPierre.

Charles Lieber, a professor of chemistry at Harvard University who has created single light-harvesting nanowires made of silicon, says that his team is also pursuing the use of other materials for making nanowires. “But there are many challenges in going from nanowire to photovoltaic,” says Lieber. He adds that comparison of approaches is difficult without data on the energy-conversion properties of each material.

Nathan Lewis, a professor of chemistry at the California Institute of Technology and an expert on nanowire structures, says that it’s too early to say which approach and materials are best. “We know nanowires work in bulk form, but we don’t know if you can make high-purity, high-quality nanowires and control all their electrical properties,” says Lewis. “There’s no theory that one works better than the other. It’s just a question of getting any of them to work.”

It’s still early days for McMaster, which in prototypes has only achieved low efficiencies–“where silicon PV was in the 1950s,” says LaPierre. But he’s optimistic that the higher-efficiency materials and the approach chosen will get results.

0 comments about this story. Start the discussion »

Credit: McMaster University

Tagged: Energy, Materials, photovoltaics, nanowire, nanotubes

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