Rare, Expensive, Mysterious: Unraveling the Platinum Group Elements

Platinum is not just for jewelry anymore. The lustrous metal and its neighbors on the periodic table are indispensable in our modern world, from your phone to your car. That’s why researchers at the National High Magnetic Field Laboratory are working to better understand how the rare elements bond with other elements to form complex molecular structures.

The Department of Energy is providing $1.185 million to continue the MagLab’s investigation of these precious metals using the lab’s world-leading Nuclear Magnetic Resonance systems.

“Our research helps DOE’s three-pillared strategy for addressing the need of the nation for these critical minerals and materials: diversifying supply, improving reuse and recycling, and finding replacement elements” said Rob Schurko, Director of the MagLab’s NMR program and a chemistry professor at Florida State University.

The platinum group elements, or PGEs, include their namesake and similar metals ruthenium, rhodium, palladium, osmium, and iridium. The names may be obscure, but their uses are not. PGEs are critical in dozens of applications. They’re used to refine crude oil and manufacture TV, computer, and cell phone screens. They can be found in dental fillings, medical implants, and chemotherapy drugs. And PGEs are a key component in the catalytic converters that clean your car’s exhaust.

Despite their widespread applications, scientists don’t fully understand how the PGE metals bond with other atoms and create complex structures at the molecular level. And because of their atomic makeup, the metals have proven difficult to analyze using Nuclear Magnetic Resonance. But MagLab researchers specialize in techniques to uncover these hard to see elements on the periodic table.

The work will be led by Schurko, along with Jochen Austchbach, chemistry professor at the University at Buffalo. The funding follows $1.1 million the duo received from the DOE for this research over the past three years.

The team will use the MagLab’s series connected hybrid magnet, at 36 Tesla, which offers the world’s strongest magnetic field for nuclear magnetic resonance. The lab also has the world’s most powerful MRI at 21 Tesla. Analysis of the PGE metals in ultra-high magnetic fields offers a "molecular fingerprint" for each compound. Scientists will study how the platinum group elements bond with nitrogen, oxygen, phosphorus, and chlorine, and will look at the structure and bonding of potential replacement metals such as manganese, iron, cobalt and copper.

The platinum group elements are not easy to come by and therefore expensive. They are among the rarest elements on earth and are mined in only a few places around the world. The United States imports 90% of its PGEs. That availability could be disrupted by economic, environmental, political, and social events, according to the U.S. Geological Survey.

The ultimate goal, by unraveling the mysteries of PGEs, is to develop ways to potentially replace the rare metals with others that are more abundant and less expensive.

“We hope this deeper understanding of the molecular properties of PGE complexes will lead to the rational design and synthesis of a new generation of complexes and materials using more abundant and cost-effective replacement metals,” Schurko said.