BYLINE: Christina Nunez
Newswise — His work has broad relevance, including making the most of difficult-to-mine rare-earth elements.
In 2023, Saw Wai Hla and a team of scientists from the U.S. Department of Energy’s (DOE) Argonne National Laboratory and several universities achieved a major milestone — using X-rays to characterize a single atom for the first time. Now Hla, a physicist in Argonne’s Materials Science division, is using the same principles to examine the properties of rare earths. These include elements such as neodymium and europium that are essential to a range of technologies but are difficult to mine.
In 2024, Hla was a Scientific Breakthrough of the Year award laureate in the physical sciences category from the Falling Walls Foundation for his groundbreaking work using X-rays. Also last year, he was awarded the Foresight Institute’s Feynman Prize in nanotechnology in the experiment category. In this interview, he talks about his latest work.
“This type of work would be almost impossible anywhere else. … It is a very rewarding career. I live with excitement.” — Argonne Physicist Saw Wai Hla
Q: What is the focus of your research at Argonne?
A: Right now, my research focus is on critical materials, especially rare earths, and the key point is to control the basic properties of individual rare-earth ions. We can study just one rare-earth ion (a charged atom) and all its properties, like the elemental type of rare-earth ion, its electronic structure, its chemical state and its magnetic properties, simultaneously. This is our capability and expertise, unmatched by others.
Q: Why study rare earths at this level of detail?
A: Our goal is to manipulate the properties of the rare-earth ion to get the desired outcomes, so that we can bypass the expensive separation procedures. Rare earths are technologically extremely important. Most high-tech components use rare earths. That includes your cellphone, high-definition TVs, telecommunications, electric vehicles, military applications and satellites.
The problem with rare earth is that it’s not like other materials like gold, for example. When you find a gold mine, you find gold with different materials, but not with similar metals like silver or copper, so it’s easy to separate them. But rare earths, often times, many of them are all together, and they all look alike from the outside. So the separation procedure is extremely expensive.
Q: How is it possible to bypass the separation process?
A: Even though the properties of rare earths’ outer structure are all the same, they have subtle interior differences. Our idea is that we can control the ions with organic ligands, which are hydrocarbons that bind to other atoms. The ligands interact with a rare-earth ion and recognize that one is not the same as the other — a bit like a parent who can tell their identical twins apart, even though they might look the same at first glance.
So, using the specially designed ligands, we hope to recognize which is which without separating them — that’s the key point. When we want to use a rare-earth ion, the ligand will select it, and that will automatically open it up for desired applications while the other one is locked so it will not be active. To do that, we must understand individual rare-earth properties, and we must be able to design those ligands.
Q: Why is Argonne a good place to do this research?
A: This type of work would be almost impossible anywhere else. It doesn’t matter how smart you are: You need the support and infrastructure, including tools such as the Advanced Photon Source (a DOE Office of Science user facility). You also need very talented people who have totally different areas of expertise. In my group, we have a chemist who specializes in synthesis, but he needs to know which design to use. We have theorists who can calculate the properties using supercomputers, but they need to confirm that their calculations are correct. We have experimentalists who measure individual properties of rare-earth ions and validate the data. You can’t be an expert in everything, so it’s important to recruit to form a team, to work together, to respect each other and to motivate younger people.
It is a very rewarding career. I live with excitement. It’s not like a normal job where you are waiting for Friday so that you have a break. I’m very enthusiastic at the start of every week, because I have data I need to analyze, and I’m looking forward to exciting results.
About the Advanced Photon Source
The U. S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne National Laboratory is one of the world’s most productive X-ray light source facilities. The APS provides high-brightness X-ray beams to a diverse community of researchers in materials science, chemistry, condensed matter physics, the life and environmental sciences, and applied research. These X-rays are ideally suited for explorations of materials and biological structures; elemental distribution; chemical, magnetic, electronic states; and a wide range of technologically important engineering systems from batteries to fuel injector sprays, all of which are the foundations of our nation’s economic, technological, and physical well-being. Each year, more than 5,000 researchers use the APS to produce over 2,000 publications detailing impactful discoveries, and solve more vital biological protein structures than users of any other X-ray light source research facility. APS scientists and engineers innovate technology that is at the heart of advancing accelerator and light-source operations. This includes the insertion devices that produce extreme-brightness X-rays prized by researchers, lenses that focus the X-rays down to a few nanometers, instrumentation that maximizes the way the X-rays interact with samples being studied, and software that gathers and manages the massive quantity of data resulting from discovery research at the APS.
This research used resources of the Advanced Photon Source, a U.S. DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology by conducting leading-edge basic and applied research in virtually every scientific discipline. Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.
The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.