Alexey Serov’s inventions pave the way for green hydrogen fuel cells

Newswise — It would be a challenge for any scientist to match Alexey Serov’s rate of inventions related to green hydrogen fuel. Serov, a researcher at the Department of Energy’s Oak Ridge National Laboratory has 84 patents with at least 35 more under review, so his electrifying pace is unlikely to slow down any time soon.

Serov’s research focuses on the materials and performance of fuel cells that power electric vehicles or buildings by converting hydrogen and oxygen into heat, water and electricity. Fuel cells create energy through an electrochemical reaction rather than by burning liquid fuel like gasoline or diesel.

Producing and using hydrogen fuel requires a somewhat circular procedure. First, a process called electrolysis splits water molecules into hydrogen and oxygen inside a device called an electrolyzer. That hydrogen then recombines with oxygen in a fuel cell to generate electricity. The interrelated nature of these steps means that improvements to either step can benefit the whole system.

When the electricity powering electrolysis comes from a clean energy source like wind or solar, the resulting product is called “green” hydrogen because its entire life cycle generates no climate-changing air pollution. Serov’s inventions enhance all the steps from generating to using green hydrogen. His research in the Energy Science and Technology Directorate spans materials, devices like electrolyzers and the catalysts that set off the reactions.

Materials to manufacturing

Both electrolyzers and fuel cells have parts similar to a battery: positively and negatively charged electrodes which trade ions through an electrolyte sandwiched between. An electrocatalyst at the surface of the electrodes triggers a chemical reaction that separates or combines hydrogen and oxygen.  

An effective electrocatalyst is key to the overall fuel cell performance. Today, electrocatalysts are usually made from expensive metals in the platinum group that are among the rarest on Earth. “Decreasing the platinum group metals decreases system efficiency and longevity, so you produce less product for the same price over time,” Serov said. “One option is improving that expensive system. But we are also looking for a more abundant and cheaper material. Even if it’s less active, we could afford using more of it.”

However, adding more material increases the size and weight of fuel cells. A large system won’t fit under the hood of a truck, although it could be used to power a home or to back up an electrical system. Serov is working on various technologies to balance these tricky tradeoffs.

Serov is unusual in not only improving fuel cell technology but also transitioning it to mass production. He is providing national leadership as deputy director of a new DOE Roll-2-Roll, or R2R, a multilab collaboration to scale up production of electrocatalyst materials as well as speed up electrode production processes.

Home to the country’s largest open-access center for battery manufacturing research and development, ORNL offers unusual opportunities to scale up laboratory discoveries using roll-to-roll and thermal analysis equipment, electron microscopes and other specialized tools in its Battery Manufacturing Facility.

The inventing of an inventor

Thanks to Serov’s mother, a physician, his childhood home in a Russian village stayed well-supplied with chemistry books. By his first year of high school, he was already hooked on laboratory experiments. A summer camp, held in his region by Moscow State University, cemented his desire to be a chemist and attend that college, where he earned several degrees before joining the faculty as an organic chemistry researcher.

When Samsung SDI recruited Serov at a job fair, he packed off to South Korea to develop innovative fuel cells, beginning his track record of patents. His subsequent doctoral research took him in the new direction of studying short-lived, highly radioactive isotopes at the University of Bern in Switzerland. That research provided the chance to be part of the first experiments determining the chemical properties of two human-made elements, copernicium and flerovium.

After South Korea and Switzerland, Serov’s next move took him to the United States. In each case, he jumped at a professional opportunity that piqued his interest, despite never having visited the country or studied the local language, except for English. Nevertheless, these choices weren’t hard for Serov: Besides his wife and two kids, his two great passions are travel and chemistry.

“My curiosity led me to making reactions, the physics of elementary particles, and real-world applications,” Serov said. “Research related to fuel cells allows me to combine those interests to solve very challenging scientific and applied problems.”

In his new job at the University of New Mexico, where Serov eventually became an associate research professor, he developed ways to make hydrogen fuel cells more affordable. “Around 2012, we found a nice class of materials that was a really good substitute for platinum in the fuel cell,” said Serov.

Made from iron, carbon and nitrogen, this material could be made anywhere from partially burned biological or other organic materials and was literally dirt cheap. Serov served as chief scientist to a startup company that licensed the innovation.

The venture was successful, but once the technology matured, Serov began pining for new discoveries. That’s what brought him to ORNL in 2021.

“Alexey is a passionate and creative scientist whose skill sets in both materials science and green energy applications bring a unique perspective that seemingly moves ideas from a very small scale to demonstration,” said Ilias Belharouak, ORNL corporate fellow and head of the lab’s electrification section. “His inventions and work on catalysis and the production and use of hydrogen have the potential to make hydrogen-powered storage and conversion devices substantial players in the decarbonization of our economy.”

At ORNL, Serov expanded his focus to include not only utilizing hydrogen fuel but producing it and using it for purposes outside transportation.

“Initially water electrolysis was mainly targeted to creating hydrogen for automobiles, especially heavy-duty trucks,” Serov said. “Now that we have a more holistic picture, we know it can be used in practically all sectors of the economy, leading to rapid decarbonization of industry.”

For example, hydrogen chemical synthesis is used in producing ammonia and other industrial chemicals. Hydrogen can be substituted for the coke used in making steel, eliminating carbon dioxide emissions. Hydrogen cells could also potentially be used to create long-term electric grid storage for the excess energy produced by solar and wind farms.

Serov represents ORNL in three other DOE hydrogen research initiatives which address various stages of hydrogen fuel cell development and rollout. For example, the Million Mile Fuel Cell Truck Consortium works to commercialize hydrogen-powered long haul trucks with zero emissions. However, those trucks won’t be practical unless hydrogen fuel prices drop. To cut costs, the H2NEW Consortium seeks to reduce the amount of the platinum group metal iridium in the catalyst while keeping fuel cell efficiency.

“To meet demand in the next decade, we’d need to use all the iridium mined per year for electrolyzers,” Serov said. “That’s impossible, since it’s also used to make components for smart phones, lasers and other products.”

Serov has been working on the iridium problem from the recycling angle, too. Efficient recycling methods could extend the supply, reducing the need to mine it. Unfortunately, today’s recycling processes take 180 to 240 days to process the iridium from electrolyzer stacks. Serov has applied for a patent on a method he developed, which dissolves metallic iridium in less than three days. He says this milestone could be his most important invention yet.

UT-Battelle manages Oak Ridge National Laboratory for DOE’s Office of Science. The single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.