Researchers discover durable yet sensitive material for detecting high-energy X-rays

X-ray technology plays a vital role in medicine and research by providing non-invasive medical imaging and information about materials. Recent advances in X-ray technology enable brighter and more intense beams and the imaging of increasingly complex systems under real-world conditions, such as the interior of working batteries.

To support these advances, researchers are working to develop X-ray detector materials that can withstand bright, high-energy X-ray radiation, especially radiation from large X-ray synchrotrons, while maintaining sensitivity and cost-effectiveness.

A team of researchers at the US Department of Energy’s (DOE) Argonne National Laboratory and their colleagues have demonstrated the exceptional performance of a new material for detecting high-energy X-ray scattering patterns. Due to its excellent robustness at extremely high X-ray flux and relatively low cost, the detector material may find wide application in synchrotron-based X-ray research.

During an X-ray scattering experiment, a beam of light particles passes through the sample under investigation. The sample scatters photons, which then hit the detector material. Analyzing X-ray scattering gives scientists insight into the structure and composition of the sample.

“Many current detector materials cannot cope with the high energies and enormous fluxes of X-rays coming out of large synchrotron facilities. Those that can are often expensive or difficult to grow or must be cooled at very low temperatures,” said Antonino Miceli, director of the Argonne Advanced Photon Source (APS ) physicist, DOE Office of Science user.

Driven by the need for better detector materials, the team analyzed the performance of cesium bromide perovskite crystals. Perovskites have simple structures with highly tunable properties, making them suitable for many applications.

The material was grown using two different methods. One method involved melting and cooling the material to induce crystal formation, which was done in the lab of Duck Young Chung, a researcher in Argonne’s Department of Materials Science. The second was a solution-based approach where crystals are grown at room temperature. This work was conducted at Northwestern University in the lab of Mercouri Kanatzidis, an Argonne senior scientist with a joint appointment at Northwestern.

“At APS beamline 11-ID-B, we evaluated crystals made using these two strategies and how they perform at a wide range of synchrotron fluxes,” Kanatzidis said. “The results were quite amazing.”

Material grown by both methods showed exceptional detection capabilities and tolerated flows up to the APS limit without problems.

“This detector material can distinguish small changes, which gives a better understanding of real materials under real conditions,” said Miceli. “It’s relatively dense compared to conventional detector materials like silicon, and it’s structured in a way that affects its electrical properties for better efficiency and sensitivity.”

High-energy X-rays allow scientists to study dynamic systems in real time. These include biological processes in cells or chemical reactions inside an engine. With the new detector’s ability to detect subtle changes during experiments, scientists can gain valuable information about the complex and fast activities of materials, facilitating faster and more detailed studies.

APS’ excellent detector materials are even more important now that the facility is undergoing a major upgrade that will increase the brightness of its beam lines by up to 500 times.

“Our group was able to grow extremely high-quality crystals thanks to Argonne’s unique capabilities and expertise, which really helped improve the material’s performance,” Chung said.

Looking to the future, the research team aims to focus on increasing production and optimizing crystal quality. They anticipate additional applications for the material, including its potential use in detecting ultrahigh-energy gamma rays with support from the DOE’s National Nuclear Security Administration.

The results of the tests were reported in Advanced materials and Advanced optical materials.