Rice University's Dr. Tour demonstrated in 2011 that graphene can be synthesized using carbon from sources as diverse as grass, Girl Scout cookies and cockroach legs.
Dr. Tour's lab has filed for multiple graphene patents, including for ribbons to reinforce composites that he says are strong enough to use in high-pressure natural-gas tanks that can be molded into cars. Patenting quickly, he says, "gives us a foothold on the technology."
One factor holding graphene back is cost. Some U.S. vendors are selling a layer of graphene on copper foil for about $60 a square inch. "It needs to be around one dollar per square inch for high-end electronic applications such as fast transistors, and for less than 10 cents per square inch for touch-screen displays," estimates Kenneth Teo, a director at the Cambridge unit of Germany's Aixtron SE AIXA.XE -0.16% that makes machines to produce graphene.
Graphene must often be combined with other materials to exploit its properties, and scientists are still trying to figure out how to do that effectively.
It also has a significant shortcoming: It can't easily be made into a switch. International Business Machines Corp. IBM +0.45% was initially optimistic about using graphene in computer chips but found electrons travel too fast in it to switch off easily, making it hard to turn current into the "ones" and "zeros" of digital code.
Labs around the world are trying to solve the problem. But for now, "we don't see graphene replacing silicon in microprocessors," says Supratik Guha, director of physical sciences at IBM's research unit, who says he remains a big proponent of graphene. IBM is a major graphene-patent filer.