Experts at the Northwestern University (NU) have recently announced that they managed to discover a way of transforming an average insulating material into a conductor, using nothing more than an average camera flash. The low-cost insulator made by oxidizing graphite powder, known as graphite oxide, was through this method converted into the highly-conductive material graphene, which is the stuff the future of the electronics industry relies on. Low-cost carbon-based transparent and flexible electronics could at least theoretically be made possible by graphene over the coming years.

The new transformation technique was created by expert Jiaxing Huang, a Northwestern University McCormick School of Engineering and Applied Science assistant professor of materials science and engineering, working together with his graduate student Laura Cote, and also with postdoctoral fellow Rodolfo Cruz-Silva. Details of the innovative process were published in the August 12th issue of the Journal of the American Chemical Society (JACS).

In previous methods of reducing graphite oxide, researchers relied heavily on high-temperature treatments and toxic chemicals to obtain graphene, in what was considered to be a very complex set of reactions. The NU team came to the new method in a “flash” of inspiration. They started wondering whether the heat emitted by an average camera flash system could be sufficient enough to cause a spontaneous heating in the oxide, and turn it into the desired graphene. “The light pulse offers very efficient heating through the photothermal process, which is rapid, energy efficient and chemical-free,” Huang says.

Additionally, in the instances when the graphite oxide is mixed with other materials, such as polymers, the photothermal process also has the beneficial side-effect of fusing the insulating polymer with the graphene sheets, which results in a welded conducting composite. “If we can make a nano circuit on a single piece of graphite oxide, it will hold great promise for patterning electronic devices,” Huang believes. The effort is now to create single graphite-oxide sheets capable of housing atom-thick circuits, something that has never been achieved.