Discovery Files

Researchers work to reduce precious metals in catalytic converters

New findings could make catalytic converters less attractive to thieves and help the environment

Precious metals in catalytic converters such as platinum, palladium and rhodium attract thieves, but University of Central Florida researchers are working to reduce the amount of precious metals the converters need — down to single atoms — while still maximizing their effectiveness.

Catalytic converters, widely introduced in American vehicles in the 1970s, use precious metals as catalysts to help scrub deadly and harmful chemicals from combustion engine exhaust. As the price of precious metals has continued to rise, so has the number of catalytic converter thefts.

The research was supported in part by the U.S. National Science Foundation.

In two recent studies, the researchers showed that they could instead use atomic platinum to control pollutants and operate the system at lower temperatures, crucial steps in removing harmful chemicals when a vehicle first starts.

In the study, published in Nature Communications, teams led by Fudong Liu and Talat Rahman constructed platinum single atoms with different atomic coordination environments at specific locations on ceria. Ceria is a metal oxide that helps improve catalytic reaction performance.

Rahman says their work demonstrates how theory and experiments working in tandem can unveil microscopic mechanisms responsible for enhancing catalytic activity and selectivity.

In the Journal of the American Chemical Society study, Liu and collaborators significantly improved the carbon monoxide purification efficiency of a platinum-ceria-alumina catalyst by 3.5 to 70 times compared to regularly used platinum catalysts.

They did that through control of coordination structures of platinum at the atomic level on an industrial-available ceria-alumina support.

The work is important, the researchers said, because it will help scientists design more active metal catalysts with 100% metal utilization efficiency for targeted environmental applications.