Bacteria for Reduction Reaction
A different approach to the graphene oxide reduction reaction was used by Professor Adarsh Sandhu and his coworkers of the Toyohashi Tech Graphene Group in a study recently published in the Journal of Physics: Conference Series. For the first time, these researchers used some bacteria to perform the reduction reaction, rather than heat or other chemical reaction. The research took place at the Toyohashi University of Technology, in Aichi, Japan – the bacteria employed were extracted and isolated from estuaries of the Toyokawa river that flows through Toyohashi City.
The Reduction Reaction Using Bacteria
In the experiments, graphene oxide sheets were attached to a silicon substrate. These sheets were subsequently placed in a solution containing the bacterial strains, and left in the dark at 28oC for three days. In the reaction, the bacteria acted as mediators for the electron transfer process; this caused the reduction of the graphene oxide into simple unmodified graphene.
The Reaction Mechanism: Why Is This Important?
Porfessor Sandhu explained the study to Decoded Science in more detail:
“We thought about using bacteria because it is known that they can transfer electrons when they breathe. Furthermore, other reports showed how an electron transfer process between bacteria and graphene oxide was possible. Our results indeed confirmed this, as we observed a reduction of the oxide.
Normally the reduction is performed with hydrazine, which can generate very toxic vapors. The system we used has a much lower impact on the environment.”
Bacteria and Oxide Reduction
The novel method of using bacteria to produce graphene is just one more way to reduce the environmental impact of manufacturing new materials. Although this process requires additional refinements, as Professor Sandhu notes, ” …as a first attempt, it was surely successful, and it tells us that this route can work. This could open new doors to alternative ways to produce graphene, not explored until now.”
Tanizawa Y., et al. Microorganism mediated synthesis of reduced graphene oxide films. (2012). Journal of Physics: Conference Series, 352, 012011. Accessed April 24, 2012.
Dreyer D.R., et al. The chemistry of graphene oxide. (2010). Chemical Society Review, 39, 228-240. Accessed April 24, 2012.
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