Bacteria-coated nanowire electrodes remove contaminants from wastewater

June 28 (UPI) -- Researchers at Cornell University have created a new cheap and efficient wastewater-cleaning electrode. The nanowire electrodes are coated in bacteria.

The electrodes are composed of electro-spun carbon nanofiber. After the nanowire is coated in a conductive polymer called PEDOT, an electrically active layer of bacteria naturally develops on the electrodes.

The Geobacter sulfurreducens bacteria enables the flow of electricity, as it digests contaminants in the wastewater.

"Electrodes are expensive to make now, and this material could bring the price of electrodes way down, making it easier to clean up polluted water," lead researcher Juan Guzman, a doctoral candidate in biological and environmental engineering at Cornell, said in a news release.

Researchers created the electrode nanofiber by pulling nano-scale filaments from a polymer solution using electric force, a technique called electrospinning. The method operates in a manner similar to a cotton candy machine. The end product recalls a metal kitchen scrubber.

The nanowire electrode was created by Meryem Pehlivaner, now a doctoral student at Northeastern University. Pehlivaner reached out to researchers at Cornell when he realized the material's waste-eating potential.

Researchers say the electrodes -- detailed in the Journal of Power Sources -- could make wastewater treatment plants more efficient, reducing their size and throughput volume.

"This defines radical collaboration," said Lars Angenent, professor of biological and environmental engineering at Cornell. "We have fiber scientists talking to environmental engineers, from two very different Cornell colleges, to create reality from an idea -- that was more or less a hunch -- that will make cleaning wastewater better and a little more inexpensive."