A research team from Northwestern University and Argonne National Laboratory has developed a remarkable “next-generation” material for nuclear radiation detection that could significantly decrease the cost of detectors compared to those currently in commercial use.
“Specifically, the high-performance material is used in a device that can detect gamma rays, weak signals given off by nuclear materials, and can easily identify individual radioactive isotopes. It has been more than 30 years since a material with this performance was developed, with the new material having the advantage of inexpensive production,” Northwestern Now, the university’s newspaper, reported.
Among the potential uses for the new device could include more widespread detectors, such as handheld versions, for nuclear weapons and materials as well as applications in biomedical imaging, astronomy, and spectroscopy.
Mercouri G. Kanatzidis, the corresponding author of the paper which was published in the journal Nature Communications is a Charles E. and Emma H. Morrison Professor of Chemistry in the Weinberg College of Arts and Sciences and also has a joint appointment with Argonne.
He said, “Governments of the world want a quick, low-cost way to detect gamma rays and nuclear radiation to fight terrorist activities, such as smuggling and dirty bombs, and the proliferation of nuclear materials. This has been a very difficult problem for scientists to solve. Now we have an exciting new semiconductor device that is inexpensive to make and works well at room temperature,” Northwestern Now reported.
“In 2013, Argonne published a scientific study noting the promise of cesium lead bromide in the form of perovskite crystals for high-energy radiation detection. Since then, researchers led by Kanatzidis, Duck Young Chung of Argonne and Constantinos Stoumpos of Northwestern have worked to purify and improve the material,” Northwestern Now reported.
The step forward was when Yihui He, a postdoctoral fellow in Kanatzidis’ group and the paper’s first author, used the improved material and reconfigured the semiconductor device. “Instead of using the same electrode on either side of the crystal, he used two different electrodes,” Northwestern Now reported, adding that “with this asymmetrical design, the device only conducts electricity when gamma rays are present.”
In comparing the new new cesium lead bromide detector to a conventional cadmium zinc telluride (CZT) detector, the research team found the results detecting gamma rays were the same.
“We achieved the same performance in two years of research and development as others did in 20 years with cadmium zinc telluride, the expensive material that is currently used,” Kanatzidis said, Northestern Now reported, adding that “it is important to know what the gamma-ray emitting material is, Kanatzidis stressed, because some materials are legal and some are illegal. Each radioactive isotope possesses its own ‘fingerprint’: a different decay behavior and a unique characteristic gamma-ray emission spectrum. The new cesium lead bromide detector can detect these fingerprints.”
The research team also tested radioactive isotopes which were successfully identified by the new detector and “also produced larger crystal samples to demonstrate the material can be scaled up,” Northwestern Now reported.
The Department of Energy, National Nuclear Security Administration, Office of Defense Nuclear Nonproliferation Research and Development (contract No. DE-AC02-06CH11357, Argonne National Laboratory) and the Department of Homeland Security ARI program (grant 2014-DN-077-ARI086-01) supported the research.
The paper, entitled “High spectral resolution of gamma-rays at room temperature by perovskite CsPbBr single crystals,” is available online at https://www.nature.com/articles/s41467-018-04073-3.
Source: thenationalherald.com