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Abstract Scintillation based X-ray detection has received great attention for its application in a wide range of areas from security to healthcare. Here, we report highly efficient X-ray scintillators with state-of-the-art performance based on an organic metal halide, ethylenebis-triphenylphosphonium manganese (II) bromide ((C38H34P2)MnBr4), which can be prepared using a facile solution growth method at room temperature to form inch sized single crystals. This zero-dimensional organic metal halide hybrid exhibits green emission peaked at 517 nm with a photoluminescence quantum efficiency of ~ 95%. Its X-ray scintillation properties are characterized with an excellent linear response to X-ray dose rate, a high light yield of ~ 80,000 photon MeV−1, and a low detection limit of 72.8 nGy s−1. X-ray imaging tests show that scintillators based on (C38H34P2)MnBr4powders provide an excellent visualization tool for X-ray radiography, and high resolution flexible scintillators can be fabricated by blending (C38H34P2)MnBr4powders with polydimethylsiloxane.
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Ceramic Cs 2 HfCl 6 : A Novel Scintillation Material for Use in Gamma Ray Spectroscopy
Abstract Single crystal scintillators have become one of the most common materials used in technologies that use radiation detectors. Unfortunately, as technology demands improved detectors, research into better single crystal scintillators has nearly reached its limit. Ceramics provide many benefits over single crystal scintillators and have emerged as a promising new production process. Recent research into ceramic scintillators has mostly dealt with oxides as they are relatively easy to handle and are typically non‐hygroscopic. Among single crystal scintillators, a trend has emerged indicating that the addition of halide ions into the crystal structure improves the light yield and energy resolution of the scintillation material but also tends to make the material hygroscopic and in some cases intrinsically radioactive. Little research is devoted to the investigation of undoped halide ceramic scintillators. Transparent halide Cs2HfCl6ceramics are developed by hot uniaxial pressing, and the scintillation properties are compared to that of its single crystal counterpart. The energy resolution of the ceramic is found to be 6.4% at 662 keV. The initial results indicate that ceramic scintillators are a viable alternative and a promising new direction in scintillator material technology.
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- Award ID(s):
- 2112556
- PAR ID:
- 10450073
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Crystal Research and Technology
- Volume:
- 56
- Issue:
- 9
- ISSN:
- 0232-1300
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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