Red Bread Mold May Be Used For Better Rechargeable Batteries

Fungi hasn't covered itself with glory so far, but a new bread mold (Neurospora crassa) may create sustainable electrochemical materials in order to produce "rechargeable batteries." They would have the ability to turn manganese into a mineral composite that has useful electrochemical properties.

"We have made electrochemically active materials using a fungal manganese biomineralization process," said Geoffrey Gadd, who led the study. "The electrochemical properties of the carbonized fungal biomass-mineral composite were tested in a supercapacitor and a lithium-ion battery, and it [the composite] was found to have excellent electrochemical properties. This system therefore suggests a novel biotechnological method for the preparation of sustainable electrochemical materials."

Gadd's team explored whether fungi could be used to create novel electrochemical materials.

"We had the idea that the decomposition of such biomineralized carbonates into oxides might provide a novel source of metal oxides that have significant electrochemical properties," Gadd said.

Even though earlier studies have tried to enhance the performance of battery with the help of alternative electrode materials, very few of them studied the potential of fungus to improve the manufacturing system.

After incubating the N. crassa fungi in media that contained urea and manganese chloride, Gadd's team saw that the long filaments of the fungi got "biomineralized and/or consumed by minerals." After they got heated, a blend of carbonized biomass and manganese oxides were left behind.

Studying the existing structures showed them that the electrochemical properties could be used in supercapacitors or lithium-ion batteries.

"We were surprised that the prepared biomass-Mn oxide composite performed so well," Gadd said, adding that it "showed an excellent cycling stability and more than 90 percent capacity was retained after 200 cycles" when compared with other reported manganese oxides and lithium-ion batteries.

The findings were published in the March 17,2016 issue of Current Biology.