Greening with Graphene: Using The Wonder Material in Green Technology0

Ysabel Yates | Wed Oct 31 2012

Graphene is the thinnest and strongest material known to man. The pure carbon substance is 100 times stronger than steel and thin enough that an ounce could cover twenty-eight football fields. It’s also transparent, electrically conductive, flexible and cheap to produce – all properties that could allow it to revolutionize a number of industries, including green technology.

The first graphene was produced in 2004 when Andre Geim and Konstantin Novoselov used sticky tape and graphite (better known as pencil lead) to separate the layers of carbon and isolate the one-atom-thick material graphene. Six years later, the scientists won the Nobel Prize in Physics for their work with the substance.

Today, the field of materials science is awash in research dedicated to finding uses for graphene, which has been touted as “the wonder material of the 21st century.”

While a lot of news about graphene involves the thin, flexible gadgets expected to be among its first commercial uses, a look at current research reveals a host of possible applications, including flexible solar panels, more efficient batteries for electric vehicles, and enhanced natural gas production.

Flexible solar panels

As Geim and Novoselov noted in their seminal 2007 paper (pdf): “The graphene ‘gold rush’ has begun.” And though there are no commercial applications for it yet, it’s important to remember that graphene is only eight years old.

Graphene is nearly transparent, electrically conductive and capable of absorbing many different wavelengths of light, giving it great potential to be used in thin, flexible solar panels that could be plastered on everything from the sides of buildings to the clothes we wear.

A number of research groups are working to realize this potential. At the beginning of the summer, physicists from the University of Florida were able to increase the efficiency of graphene solar cells from 2.9 percent to 8.6 percent. The researchers believe if they can reach efficiencies of 10 percent, the cells could be competitive commercially.

Better batteries

Graphene could help advance electric vehicles by leading to a new class of batteries that are small and quick to charge.

Engineers at Rensselaer Polytechnic Institute recently created a new device from graphene that can charge 10 times faster than the graphite anodes used in conventional lithium-ion batteries. To develop the device, researchers created a sheet of paper from graphene, and then zapped it with a laser or camera flash to put cracks and other imperfections in it. These imperfections allow the device to rapidly take up or discharge large amounts of energy.

According to the researchers, these results could “make a significant impact on the development of new batteries and electrical systems for electric automobiles and portable electronics applications.”

Improved natural gas production and reduced CO2 emissions

Other researchers are looking to graphene’s unique porous structure for potential applications.

At the University of Colorado, researchers found that graphene’s structure renders it impermeable to all standard gases. Because of this, it can work like a “molecular sieve” to separate gas molecules.

The researchers believe this could lead to energy-efficient filters that enhance natural gas production, or membranes for power plant exhaust pipes that reduce carbon dioxide emissions.

Top image: The structure of graphene. Courtesy Wikimedia Commons user AlexanderAlUS.