Researchers Infuse Bacteria with Silver to Boost Power Efficiency in Fuel Cells
A UCLA-led team of engineers and chemists had a significant advancement in developing microbial fuel cells-a modern technology that uses natural bacteria to remove electrons from organic matter in wastewater to produce electrical currents. Research detailing the innovation was just recently released in Science.
“Living energy-recovery systems using microorganisms inhabiting in wastewater offer a one-two punch for environmental sustainability efforts,” claimed co-corresponding author Yu Huang, a teacher and also chair of the Materials Scientific Research and Engineering Department at the UCLA Samueli College of Engineering. “The natural populations of bacteria can assist decontaminating groundwater by breaking down harmful chemical compounds. Now, our research study likewise shows a practical method to secure renewable energy from this process.”.
The team concentrated on the bacteria genus Shewanella, which has been immensely studied for its energy-generation capabilities. Regardless of oxygen levels, they can expand and thrive in all kinds of settings-including dirt, wastewater, and saltwater.
Shewanella species naturally decompose natural excrement into smaller molecules, with electrons resulting from the metabolic process. When the bacteria develop as films on electrodes, a few electrons can be recorded, forming a microbial fuel cell that generates electricity.
However, Shewanella oneidensis powered microbial fuel cells, previously, have not caught enough currents from the bacteria to make the technology sensible for industrial use. Few electrons could move fast enough to leave the bacteria’s membranes and enter the electrodes to supply enough electrical currents and power.
To address this problem, the researchers included nanoparticles of silver to electrodes made of a type of graphene oxide. The nanoparticles launch silver ions, which bacteria reduce to silver nanoparticles utilizing electrons produced from their metabolic process and afterward include right into their cells. When inside the bacteria, the silver fragments act as microscopic transmission cables, catching even more electrons generated by the bacteria.
“Adding the silver nanoparticles right into the bacteria is like producing a specialized express lane for electrons, which allows us to extract even more electrons and at faster rates,” said Xiangfeng Duan, the research’s other corresponding author and a professor of chemistry and also biochemistry at UCLA.
With significantly enhanced electron transport efficiency, the resulting silver-infused Shewanella film yields more outstanding than 80% of the metabolic electrons to an external circuit, producing power of 0.66 milliwatts per square centimeter- over double the previous best for microbial-based fuel cells.
With the augmented current and better efficiencies, the research study, which the Workplace of Naval Study supported, revealed that fuel cells powered by silver-Shewanella hybrid bacteria might lead the way for acceptable power outcomes in practical settings.
Originally published on Scitechdaily.com. Read the original article.
Reference: Silver nanoparticles boost charge extraction efficiency in Shewanella microbial fuel cells, Science (2021). DOI: 10.1126/science.abf3427
