A catalyst for more efficient green hydrogen production – BIOENGINEER.ORG

The climate crisis requires increased use of renewable energy sources such as solar and wind, but with occasional availability, scalable energy storage is a challenge.

The climate crisis requires increased use of renewable energy sources such as solar and wind, but with occasional availability, scalable energy storage is a challenge.

Hydrogen – especially carbon-free green hydrogen – has emerged as a promising clean energy source and option for storing renewable energy such as sun and wind. It does not add carbon emissions to the atmosphere, but is currently expensive and complex to create.

One way to produce green hydrogen is by electrochemical cleavage of water. This process involves conducting electricity through water in the presence of a catalyst (reaction-promoting substances) to produce hydrogen and oxygen.

Researchers from the Georgia Institute of Technology and the Georgia Tech Research Institute (GTRI) have developed a new water splitting process and material that maximizes green hydrogen production efficiency, making it an affordable and affordable option for industrial partners looking to switch to green hydrogen for renewable energy storage instead conventional hydrogen production from carbon-emitting natural gas.

Georgia Tech’s findings come when climate experts agree that hydrogen will be critical for the world’s largest industrial sectors to achieve its net zero-emission targets. Last summer, the Biden administration set a goal to reduce the price of pure hydrogen by 80% in a decade. Called the Hydrogen Shot, an initiative led by the Department of Energy seeks to reduce the price of “pure” or green hydrogen to $ 1 per kilogram by 2030.

Scientists hope to replace natural gas and coal, which are used today to store additional electricity at the grid level, with green hydrogen because it does not contribute to carbon emissions, making it a more environmentally friendly means of storing renewable electricity. The focus of their research is electrolysis, ie the process of using electricity to split water into hydrogen and oxygen.

Less expensive, more durable materials

Georgia Tech’s research team hopes to make green hydrogen cheaper and more durable using hybrid electrocatalyst materials. Today, the process relies on expensive components of precious metals such as platinum and iridium, preferred catalysts for hydrogen production by electrolysis in scale. These elements are expensive and rare, which has stopped the step of replacing gas with hydrogen-based energy. In fact, green hydrogen accounted for less than 1% of annual hydrogen production in 2020, largely because of this cost, according to market research firm Wood Mackenzie.

“Our work will reduce the use of these precious metals, increasing their activity as well as usability,” said lead researcher Seung Woo Lee, associate professor at the George W. Woodruff School of Mechanical Engineering and expert in electrochemical energy storage and conversion systems.

In a study published in a journal Applied Catalysis B: Ecological and Energy and environmental science, Lee and his team highlighted the interactions between metal nanoparticles and metal oxide to support the design of high performance hybrid catalysts.

“We designed a new class of catalyst where we came up with a better oxide substrate that uses fewer precious elements,” Lee said. “These hybrid catalysts have shown superior performance for both oxygen and hydrogen (cleavage).”

Nanometer analysis

Their work relied on computing and modeling from a research partner, the Korean Institute for Energy Research, and X-ray measurements from Kyungpook National University and Oregon State University, who used the country’s synchrotron, a super X-ray the size of a football field.

“Using X-rays, we can monitor structural changes in the catalyst during the water cleavage process, on a nanometer scale,” Lee explained. “We can investigate their oxidative state or atomic configurations under operating conditions.”

Jinho Park, a scientist at GTRI and a leading research researcher, said the research could help reduce the cost barrier of equipment used in hydrogen production. In addition to the development of hybrid catalysts, the researchers fine-tuned the ability to control the shape of the catalyst as well as the interaction of the metal. The key priorities were to reduce the use of catalysts in the system and at the same time increase its durability as the catalyst accounts for a large share of equipment costs.

“We want to use this catalyst for a long time without deteriorating its performance,” he said. “Our research is not only focused on making a new catalyst, but also on understanding the mechanics of the reaction behind it. We believe our efforts will help support a thorough understanding of the water-splitting reaction on catalysts and provide significant insights to other researchers in the field, ”Park said.

The shape of the catalyst is important

The key finding, according to Park, was the role of catalyst forms in hydrogen production. “The surface structure of the catalyst is very important in determining whether it is optimized for hydrogen production. That is why we are trying to control the shape of the catalyst as well as the interaction between the metal and the substrate material, ”he said.

Park said some of the key applications that take precedence include hydrogen stations for fuel cell electric vehicles, which today operate only in the state of California, and microgrids, a new community approach to designing and running electricity networks that rely on backup to renewable energy power.

While research for XYZ is largely ongoing, the team is currently working with partners to research new materials for efficient hydrogen production using artificial intelligence (AI).

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Georgia Institute of Technology, or Georgia Tech, is the top 10 public research universities in the development of leaders who advance technology and improve the human condition. The institute offers business, computer, design, engineering, liberal and science degrees. Its nearly 44,000 students, representing 50 states and 149 countries, study on the main campus in Atlanta, on campuses in France and China, and through distance learning and online. As a leading technology university, Georgia Tech is a driver of economic development for Georgia, the Southeast and the state, spending more than $ 1 billion annually in research for government, industry and society.

STATEMENTS: M. Kim, J. Park, et. al, “The role of surface steps in the activation of oxygen surface sites on Ir nanocrystals for the reaction of oxygen evolution in acidic media,” (Applied catalysis B: environment, 2021) https://doi.org/10.1039/d0ee02935a
M. Kim, B. Hyun-Kim, S. Woo Lee, et. al, “Understanding synergistic metal-oxide interactions in situ of dissolved metal nanoparticles on a pyrochloride oxide substrate for improved water cleavage,” (Energy environment. science, 2021.) https://doi.org/10.1016/j.apcatb.2021.120834

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