A recent study published last week tells of a rather significant scientific finding that can improve the power efficiency in fuel cells.
Researchers at the University of California - Los Angeles (UCLA) studying natural bacteria have found a way to use its metabolic process as a tool to extract electrons from wastewater and generate electricity.
This breakthrough has the potential to open up a world of possibilities as individuals around the globe are searching for sustainable alternatives to lessen the negative outcome of climate change.
The Basics of Fuel Cells
Before we discuss the study, we must first understand what fuel cells are and how they work.
According to the United States Department of Energy, fuel cells use the chemical energy of a given fuel to produce electricity. When conducted successfully, they have a wide scale of applications ranging anywhere from a giant power plant to a personal cellphone.
Compared to the combustion-based technology that is frequently used in vehicles and large power plants, fuel cells are far more efficient and produce little to no emissions.
Though similar to batteries, fuel cells do not need recharging as they can operate continuously as long as they are supplied with an accurate fuel source. A fuel cell is comprised of an anode, cathode, and electrolyte membrane. A given fuel source will begin the process by passing through the anode, where a catalyst will split it into negatively charged electrons and positively charged protons. These protons and electrons will then be separated and transferred to two different parts of the fuel cell. The electrons make their way toward a circuit -electrode- which will create an electric charge. Meanwhile, oxygen is being transmitted to the cathode.
The electrons will finally make their way through the circuit again and combine with the oxygen and protons to create the fuel cell's by-product, water, and heat.
Though it may sound a little complicated, the process of fuel cells is rather cut and dry. Nevertheless, Engineers and Chemists at UCLA have taken this well-known process and put their own spin on it to attempt energy generation via bacteria.
When conducting this study, the team used the bacteria genus Shewanella, which can thrive in many wet conditions and therefore is abundant throughout the globe. In this case, the researchers obtained the bacteria from wastewater in marine environments. Previously, Shewanella has undergone examination as a potential for generating energy, though nothing of significance has resulted from such trials.
During the metabolic process of which Shewanella is breaking down organic matter, electrons occur as a by-product. After the electrons form, bacteria will grow on them, which, in some cases, will create a small fuel cell, thus producing an electric charge.
Though this method has been previously studied, it has never been as successful as UCLA was because the formed electrons couldn't move quickly enough to make it to the electrode. Because of this, the energy that was captured wasn't enough for industrial use. After examining this discrepancy, the researchers incorporated silver nanoparticles into the electrodes to help capture the electrons produced by the bacteria.
"Adding the silver nanoparticles into the bacteria is like creating a dedicated express lane for electrons, which enabled us to extract more electrons and at faster speeds," said Xiangfeng Duan, a professor of chemistry and biochemistry at UCLA and the study's corresponding author. Their process worked rather successfully as they are now able to capture more than 80% of the electrons to the external electrode thanks to the added silver.
This breakthrough has also doubled the efficiency output of previous microbial-based fuel cells by generating power of 0.66 milliwatts per square centimeter.
Producing an energy source isn't the only sustainable outcome of this process, as the removal of certain bacteria from wastewater can aid in a thriving ecosystem. Another corresponding author and professor at the Materials Science and Engineering Department at the UCLA Samueli School of Engineering, Yu Huang, says that "Living energy-recovery systems utilizing bacteria found in wastewater offer a one-two punch for environmental sustainability efforts. The natural populations of bacteria can help decontaminate groundwater by breaking down harmful chemical compounds. Now, our research also shows a practical way to harness renewable energy from this process."
This breakthrough is supported by the Office of Naval Research and is assumed to influence future studies and fuel cell trials. Thus, the discovery could ultimately result in an array of alternative energy options to power the globe and positively influence the current state of climate change.
Given these points, we must take this research as a win and as an example of all the potential sustainable alternatives that have yet to reach mainstream knowledge. From that, we can conclude an abundance of solutions to climate change that are being revealed, presently leaving a wealth of hope for the future of humankind.