Over 90% of the devices we use every day depend on battery power supply. Since the onset of a digital era, solid and metal-air energy has significantly skyrocket in demand as mineral deposits used to power our gadgets become rare.
Meanwhile, some scientists have come to propose a better and much cheaper battery catalyst, which turned out to be a plant you consume everyday, spinach!
The new high-performance catalyst from spinach was developed by a group of researchers from American University.
The most common and current battery cathode catalyst is Platinum, however, being a rare earth element, it poses quite substantial risks, including financial and environmental risks.
As the earth continues to dwindle in its resources, researchers have begun a quest to find sustainable means to power our own world by developing clean and environmental-friendly battery technology.
A recent study published in the American Chemical Society’s open-source journal ACS Omega proposes that spinach catalyst can be one of the solution.
The newly discovered catalyst has shown promises in fuel-cell and metal-air battery technology. However, both of them continue to operate under the anode/cathode/electrolyte paradigm of the current batteries.
Scientifically, electrons travel within a battery from one electrode (anode), through the battery’s electrolyte (either powder or liquid barrier) to another electrode (cathode). The anode releases electrons through a process called, oxidation, whereas the cathode receives these electrons through an oxygen reduction reaction process. The whole of this process is then known as redox reaction.
For the electrons to return back to the anode, it requires a “load” provided by an external device, such as torch or mobile device.
The electrons then travel out of the cathode’s positive terminal to the device the return back to the battery’s negative anode terminal. This process is continuously repeated through the battery-device circuit.
NOTE: While charging your battery, the process is vice versa. Electrons go in the opposite direction connected to the charger.
Fuel-cell and metal-air batteries are designed to use the surrounding air outside the battery as their cathode, which is abundant enough to prompt the oxygen reduction reaction required.
The downside of these platinum-based catalyst batteries is that they are too expensive and less environmental-friendly.
The new study reveals that, “the lack of long-term stability and the vulnerability to surface poisoning by various chemicals such as methanol and carbon monoxide, call for the development of non-Pt group metal (NPGM) catalysts.”
Due to common catalysts’ toxic nature, scientists have been trying to find non-toxic, carbon-based catalysts alternatives that are less expensive and have a faster chemical reaction.
According to the research report from American University’s Department of Chemistry, Professor Shouzhong Zou states that,
“The method we tested can produce highly active, carbon-based catalysts from spinach, which is a renewable biomass. In fact, we believe it outperforms commercial platinum catalysts in both activity and stability. The catalysts are potentially applicable in hydrogen fuel cells and metal-air batteries.”
Many different plants have been tried in the catalyst research project, including, rice and cattails, however, Professor Shouzhong Zou believes that spinach merits to be the candidate for the catalyst research since it has a few things which are important in the research.
Spinach is mainly rich in iron and nitrogen, both of which are essential catalyst ingredients.
Spinach is easy and inexpensive to grow, and can be produced in abundance.
HOW THE PROCESS TOOK OFF
Professor Shouzhong Zou and his students developed spinach-based carbon nanosheets that are a thousand times thinner than human hair.
To begin the process, the researchers washed, juiced, and freeze-dried the vegetable before grinding it by hand into a fine powder using mortar and pestle.
Next, the spinach powder was dissolved and mixed with melamine, sodium chloride and potassium chloride in water and cooked together at 120°C. This mixture was then rapid-cooled in liquid nitrogen and freeze-dried. Then it was pyrolyzed twice.
“This work suggests that sustainable catalysts can be made for an oxygen reduction reaction from natural resources.” States Professor Shouzhong Zou.
The next phase of the process is to test the spinach catalyst in prototype fuel cells to assess its performance in action.