Researchers uncover key mechanisms for sustainable ammonia production

Collaborators from Virginia Tech and a research team from the University of Central Florida have published key findings on the electrochemical synthesis of ammonia, advancing sustainable fertilizer research and supporting global food safety efforts. I’m here.

Ammonia, a compound of nitrogen and hydrogen, is an essential component of many fertilizers for food production. However, its dominant production method, the Haber-Bosch process, is energy and fuel intensive, consuming 3% to 5% of global natural gas production and contributing more than 1% of global carbon emissions. occupies.

use of metal ruthenium As catalyst, researchers have identified a more sustainable production method: the most efficient way to produce ammonia electrochemically.This method of production requires less power renewable resourcesUsing power such as solar and wind power electrochemical synthesissays the researchers.

The results of this survey were recently ACS Energy Letter.

Much research has been done on the electrochemical production of ammonia, but the underlying mechanisms are still poorly understood, researchers say. However, the new study helps provide a clearer picture of the reaction mechanism, says study co-author Xiaofeng Feng, a professor in UCF’s Department of Physics.

“The results of this detailed study can provide important guidance to researchers on how to design more efficient catalysts for sustainable ammonia production,” says Feng.

how they worked

The optimal bonding strength of ruthenium with reaction intermediates makes it one of the most active catalysts for nitrogen reduction reactions, combining nitrogen and hydrogen from water molecules to form ammonia.

use atomic layer depositionresearchers were able to maintain precise control over the synthesized nanomaterials at the atomic scale, enabling testing of ruthenium nanoparticles in the range of 2–8 nanometers.

Researchers discovered a special arrangement of ruthenium surface atoms in layering the ruthenium atoms into the catalyst structure._Five Step site – was the most active site for the electrochemical nitrogen reduction reaction.

Unlike other sites, D_Five Stepsites have a “perfect balance” in favor of *N formation₂H intermediate, not poisoned by *NH (new molecule adsorbs and cannot react)₂ In the middle, researchers say.

Therefore, ruthenium nanoparticles with a size of ~4 nm were found to have the optimal catalytic performance for the nitrogen reduction reaction. The activity peaked at 4 nm and decreased five-fold when the particle size was doubled, demonstrating the significant effect of ruthenium. particle size About catalysis.

The researchers’ previous work to improve the efficiency of the electrochemical production of ammonia aided the current work by providing an understanding of the mechanism and research methodology.

Joint research

The new research is a collaboration between three research teams.

Feng and his students characterized ruthenium samples and studied them as catalysts for the electrochemical production of ammonia. His Parag Banerjee, co-author of the paper and professor in the Department of Materials Science and Engineering at UCF, and his students focused on the precise synthesis of ruthenium metal nanoparticles in Banerjee’s lab.

In addition, Professor Hongliang Xin and his students at Virginia Tech conducted computational studies for modeling and identification. atomic structure It has the best catalytic performance.

The researchers plan to collaborate further to develop more complex and efficient materials using atomic layer deposition for sustainable ammonia production, Feng says. They also implement catalytic materials in advanced electrolyzers to improve the yield and efficiency of electrification. ammonia manufacturing.