The material may replace silicon as a basis for modern electronics

Mar 22, 2012 10:59 GMT  ·  By

Naturally-occurring processes taking place on the surface of bacterial cells can contribute to producing graphene, a 2D carbon compound that has extensive practical applications. The discovery was made by a group of Japanese experts at the Toyohashi University of Technology (Toyohashi Tech).

The material is obtained from graphene oxide (GO), which needs to be reduced before the single-atom-thick sheets of carbon atoms are obtained. Until now, the process involved the use of hydrazine, a chemical that limited the ability to produce the material at a large scale.

Being unable to synthesize large amounts of graphene on demand is one of the main reasons why the compound has yet to enter mainstream use. Since it was first produced, back in 2004, more than 3,000 research papers have been published on its properties and potential uses.

Graphene is the strongest material ever obtained, a feat that stems from the hexagonal arrangement of its atoms. Ironically, it is obtained from graphite, the material that makes up the lead in pencils.

In fact, the University of Manchester researchers who first obtained the material did so by putting adhesive tape on the tip of a pencil, and then peeling off very thin layers of graphite. Upon further separation, they obtained graphene.

The carbon compound has some amazing physical and chemical properties, particularly when it comes to handling electrical currents flowing through it. In addition, it can also be used as a coating, armor, or as a hydrophobic layer on other materials.

Physicists say that it can also be used to create carbon nanotubes, by rolling a sheet on graphene onto itself. Toyohashi Tech Graphene Research Group researchers were therefore very interesting in figuring out how to produce large amounts of the stuff through oxidation.

Rather than using hydrazine, they turned to nature. From a nearby river, they extracted bacteria that proved to be just as effective as the synthetic chemical in reducing GO. The researchers are based at the Electronics Inspired Interdisciplinary Research Institute (EIIRIS).

Unlike hydrazine vapors, which are highly toxic, the bacteria produce no harmful compounds as they reduce graphene oxide to their 2D versions. The fact that the microorganisms can indeed fulfill this role was verified using raman scattering measurements.

The group now plans to refine its approach, in hopes of developing a scalable method for producing graphene efficiently. Details of the work appear online, in the Journal of Physics: Conference Series.