Green Fabrication of Sulfonium-Containing Bismuth Materials for High-Sensitivity X-Ray Detection.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40207598.
- Also identified by DOI 10.1002/adma.202418626 and PMC identifier 12177852.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Organic-inorganic hybrid materials based on lead and bismuth have recently been proposed as novel X- and gamma-ray detectors for medical imaging, non-destructive testing, and security, due to their high atomic numbers and facile preparation compared to traditional materials like amorphous selenium and Cd(Zn)Te. However, challenges related to device operation, excessively high dark currents, and long-term stability have delayed commercialization. Here, two novel semiconductors incorporating stable sulfonium cations are presented, [(CH<sub>3</sub>CH<sub>2</sub>)<sub>3</sub>S]<sub>6</sub>Bi<sub>8</sub>I<sub>30</sub> and [(CH<sub>3</sub>CH<sub>2</sub>)<sub>3</sub>S]AgBiI<sub>5</sub>, synthesized via solvent-free ball milling and fabricated into dense polycrystalline pellets using cold isostatic compression, two techniques that can easily be upscaled, for X-ray detection application. The fabricated detectors exhibit exceptional sensitivities (14 100-15 190 µC Gy<sub>air</sub> <sup>-1</sup> cm<sup>-2</sup>) and low detection limits (90 nGy<sub>air</sub> s<sup>-1</sup> for [(CH<sub>3</sub>CH<sub>2</sub>)<sub>3</sub>S]<sub>6</sub>Bi<sub>8</sub>I<sub>30</sub> and 78 nGy<sub>air</sub> s<sup>-1</sup> for [(CH<sub>3</sub>CH<sub>2</sub>)<sub>3</sub>S]AgBiI<sub>5</sub>), far surpassing current commercial detectors. Notably, they maintain performance after 9 months of ambient storage. The findings highlight [(CH<sub>3</sub>CH<sub>2</sub>)<sub>3</sub>S]<sub>6</sub>Bi<sub>8</sub>I<sub>30</sub> and [(CH<sub>3</sub>CH<sub>2</sub>)<sub>3</sub>S]AgBiI<sub>5</sub> as scalable, cost-effective and highly stable alternatives to traditional semiconductor materials, offering great potential as X-ray detectors in medical and security applications.