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High-performance and low-cost metal halide perovskite scintillator materials have important applications in X-ray detection and imaging. However, large-sized perovskite scintillator panel with high transmittance, low toxicity and long-term stability is still lacking. Herein, Eu2+ doped cesium alkaline earth chloride nanocrystals (Eu2+: CsCaCl 3 , Eu2+: CsSrCl 3 , and Eu2+: Cs 2 BaCl 4 NCs) embedded in glasses through conventional melt-quenching and subsequent heat-treatment were developed. These NCs doped glasses exhibited highly efficient and narrowband photoluminescence in blue region. Benefitting from the large X-ray absorption coefficient and high photoluminescence quantum yied, these Eu2+: CsCaCl 3 NCs doped glass scintillator shows light yield of ∼9300 photons/MeV, detection limit of ∼213.8 μGy/s, and spatial resolution of 30.0 lp/mm. These results demonstrated that glasses containing Eu2+ doped cesium alkaline earth chloride nanocrystals are promising for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

The growth of the CsI(Tl) scintillators deposited on glass substrates with proper wavelength matching the mainstream semiconductor circuits is crucial for X-ray imaging industry. But the coupling loss between the scintillators and silicon based photo sensors has limited the performance. So fabricating CsI(Tl) films on monocrystalline silicon is greatly important for next-generation high performance X-ray image devices. However, the lattice and thermal mismatch between CsI(Tl) and Si always deteriorates the morphology and structure, and thus degrades the property of the CsI(Tl) scintillation converters. Here, by utilizing crystalline graphene(Gr) as a buffer layer, the van der Waals epitaxial growth of CsI(Tl) film on Si(111) substrate is reported and its advanced applications are demonstrated. The introduced graphene buffer layer extremely frees the stress between CsI(Tl) and Si substrate. Therefore, the CsI(Tl) films show perfect micro-columnar and crystalline structures, and then, exhibit much higher light output and signal to noise ratio, and better modulation transfer functions and a bar pattern X-ray image compared to that on bare Si(111) substrate. This facile method not only lays the foundation for the epitaxy of the alkali halide crystals, including CsI(Tl), onto Si-based detectors and its applications in radiation detection, but also may broaden a new perspective of deposition of CsI(Tl) scintillators into flexible substrates. [ABSTRACT FROM AUTHOR]

Micron/sub-micron hard X-ray imaging is an important development direction of X-ray detection technology. Scintillation screens with excellent X-ray stopping power and high light output are desired to obtain good imaging quality. Europium-doped lutetium oxide (Lu 2 O 3 :Eu) film with micro-columnar structure is an ideal candidate for this application. In this study, micro-columnar structured Lu 2 O 3 :Eu films were prepared on quartz glass substrates by laser chemical vapor deposition (LCVD) method. The influences of preparation conditions on structure and morphology properties of films were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Photoluminescence and scintillation properties of the films, including photoluminescence excitation (PLE), photoluminescence (PL), PL decay, X-ray excitation luminescence (XEL), and afterglow curves, were recorded. The relationships between structure, morphology, luminescence properties of films, and preparation conditions were investigated and discussed as well. The preparation conditions include laser power, oxygen flow rate, and precursor evaporation temperature. In addition, dual-layer Lu 2 O 3 :Eu film was prepared for the first time by just turning off the laser. [ABSTRACT FROM AUTHOR]

Compared with single-crystal scintillator, the glass scintillators have the benefits of low cost, big size, straightforward manufacturing method, and adjustable component. In this work, a succession of diaphanous gallogermanate glass scintillators doped with Tb3+ or Eu3+ were manufactured using melt-quenching technique. The thermal, structural, photoluminescent, and scintillating properties were studied. For photoluminescent properties, 12 mol% Tb3+-doped glass sample has high internal quantum efficiency (87.8%) and no obvious concentration quenching phenomenon can be observed. For scintillating properties, the optimal doping concentration of Tb3+ and Eu3+ are 4 mol% and 8 mol%, respectively. The integral intensity of X-ray excited luminescence of Tb3+-doped sample is 73.1% of that of Bi 4 Ge 3 O 12 scintillator, while the ratio of Eu3+-doped sample is 26.5%. The radiation damage of 4 mol% Tb3+-doped sample resulted by high power X-ray could be repaired through heat-treatment, while 8 mol% Eu3+-doped sample exhibits fine stability that the transmittance keeps constant after exposed to high power X-ray. Our research indicates Tb3+ or Eu3+ doped gallogermanate glass might be candidate for X-ray detection of slow events. [ABSTRACT FROM AUTHOR]

Pr3+ doped high density germanate glasses were prepared by the melt-quenching method. The physical and luminescent properties were investigated. The glass containing BaF 2 represented maximum phonon energy of 810 cm−1, and the glass density was greater than 6 g/cm3. The glass exhibited good radiation resistance under 2 h of X-ray irradiation. Intense blue, green emissions and weak red emissions were observed when the glass was excited by X-ray, and the blue fluorescence lifetimes were in the range of 9.15–12.59 μs The results show that Pr3+ doped germanate glass could be a potential scintillating material in the field of X-ray detection for fast events. [ABSTRACT FROM AUTHOR]

In recent years, copper-based halide scintillators have attracted tremendous attention due to their excellent luminescent properties and low manufacturing costs. Herein, a high-performance and low-cost Cs 5 Cu 3 Cl 6 I 2 scintillator is prepared by simple mechanical grinding. The mixed-halide Cs 5 Cu 3 Cl 6 I 2 phosphor exhibits a blue emission centered at 475 nm with a large stokes shift, originating from the self-trapped exciton emission of Cu sites. The photoluminescence quantum yield (PLQY) of Cs 5 Cu 3 Cl 6 I 2 can be increased to 88.4% from 20.4% by the efficient suppression of the anion vacancy defects. In addition, the Cs 5 Cu 3 Cl 6 I 2 scintillator shows a high steady-state X-ray to light conversion efficiency of about 57000 photons/MeV, good X-ray linear response, and low detection limit of 71.9 nGy air /s. The X-ray imaging results based on the Cs 5 Cu 3 Cl 6 I 2 scintillator screen display a high spatial resolution of 9.0 line-pairs per millimeter (lp/mm). Furthermore, Cs 5 Cu 3 Cl 6 I 2 exhibits good radiation stability under a total dose of 113.58 Gy air. Overall, the Cs 5 Cu 3 Cl 6 I 2 scintillator prepared by mechanical grinding method has the advantages of low cost, high efficiency, and good radiation resistance, suggesting its huge potential in X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

The development of Eu2+-activated oxide materials with high efficiency, fast decay and narrow bandwidth emission in the visible region is still challenging for the field of luminescence and scintillation applications. Generally, Eu2+ in oxide hosts can emit intense and broad 5d-4f emission in the visible region, but efficient emitting with stable bivalence of Eu is rare in inorganic oxide system. In this work, a series of ASL:Eu2+ (Sr 1-x La x Mg x Al 12-x O 19) powder samples with various La, Mg doping ratios were designed and synthesized to modulate the UV or X-ray excited luminescence properties, including redshift, quantum yield, and decaying lifetime. Moreover, an ASL:Eu2+ crystal with the optimal ratio x = 1/3 was grown, its scintillation performance was compared with standard Bi 4 Ge 3 O 12 crystal sample and evaluated in detail. These results indicate that the ASL:Eu2+ crystal is potential scintillator as a kind of X-ray detection and provide a reference for the further development of high-performance Eu-activated oxide scintillation materials. • The La, Mg dopants in SrAl 12 O 19 host promotes the red shift of Eu2+ emission under UV excitation. • The ASL:Eu2+ shows the self-trapped excitons radiation in XEL spectra. • The light yield of the as-grown ASL:Eu2+ crystal was determine to be 111.6 p.e./MeV. [ABSTRACT FROM AUTHOR]

A simple method of in-situ growth using anodized aluminum oxide templates is used to prepare a high-resolution pixelated scintillator array Cs 5 Cu 3 Cl 6 I 2 with enhanced light direction limitation for X-ray imaging, The Cs 5 Cu 3 Cl 6 I 2 @AAO film performs excellent stability under long-term X-ray irradiation, making it a reliable option for cost-effective pixelated indirect X-ray imaging. [Display omitted] • A perovskite array scintillation film Cs 5 Cu 3 Cl 6 I 2 @AAO via an in-situ growth strategy was fabricated. • A spatial resolution of approximately 20 lp mm−1 and a detection limit of 0.152 μGy·s−1 were achieved. • Excellent stability under long-term X-ray irradiation of Cs 5 Cu 3 Cl 6 I 2 @AAO was studied. Lead-free halide perovskites have shown promising application for indirect X-ray detection as fascinating scintillator. The fabrication of pixelated scintillator films leveraging directional confinement allows high-resolution imaging, yet process complexity and the potential crystal structure damage pose challenges that compromises the corresponding scintillator performance. In this work, a facile in-situ strategy for growing scintillation perovskite of Cs 5 Cu 3 Cl 6 I 2 within anodic aluminum oxide (AAO) membrane is developed as scintillator Cs 5 Cu 3 Cl 6 I 2 @AAO film. The as-fabricated pixelated scintillator array with an enhanced light directional confinement for high-resolution X-ray imaging is demonstrated. The corresponding film achieves a spatial resolution of approximately 20 lp mm−1 and a detection limit of 0.152 Gy·s−1. Moreover, the Cs 5 Cu 3 Cl 6 I 2 @AAO film performs excellent stability under long-term X-ray irradiation, making it a reliable option for cost-effective pixelated indirect X-ray imaging. [ABSTRACT FROM AUTHOR]

The perovskite scintillators have been extensively studied recently for their merits of tunable emission spectra and simple preparation processes. However, the practical applications of perovskite scintillator-based X-ray image sensor are still impeded by inadequate radioluminescence, poor environmental stability, and low imaging resolution. Herein, we demonstrate a scalable co-firing method to fabricate high-quality lead-free Cs 3 Cu 2 I 5 perovskite scintillator and an Indium (In)-doping strategy is introduced to enhance its radioluminescence performance at the same time. The In-doped Cs 3 Cu 2 I 5 obtains a high PLQY of 77.9% and a relative light output of 53372 ph/MeV, which are 0.34 and 1.08 times higher than those of the undoped counterpart, respectively. The X-ray detection limit of the In:Cs 3 Cu 2 I 5 can reach 150.55 nGy air /s, 36.53 times lower than the requirement for X-ray medical diagnosis. The synthesized scintillator also shows superior stability under continuous high dose X-ray irradiation of 6800 μGy air /s for 120 minutes, maintaining 95% of its initial radioluminescence intensity. Furthermore, a large-area (300 cm2) flexible perovskite scintillator film is prepared, which owns a much competitive resolution of 10 lp/mm and less distortion in X-ray imaging. This work provides a practical path for the wide application of perovskite scintillator in the field of X-ray detection and imaging in near future. [Display omitted] • A co-firing method for lead-free indium doped Cs 3 Cu 2 I 5 perovskite scintillators has been proposed. • The indium doped Cs 3 Cu 2 I 5 shows superior environmental and radiation stability. • A large-area flexible scintillator film is prepared for high-resolution imaging. [ABSTRACT FROM AUTHOR]

[Display omitted] • MAPbBr 3 NCs are in-situ space-confined encapsulated in metal–organic frameworks. • bMOF⊃MAPbBr 3 realizes room-temperature scintillation and exceptional X-ray imaging. • bMOF⊃MAPbBr 3 shows enhanced stability against various stimuli and X-rays. • The role of the MOF and the mechanism of improved performance are elucidated. The development of perovskite nanocrystals (NCs) based composites with enhanced stability and exceptional photoelectric properties is of great significance for their application in scintillators for X-ray imaging, but it remains challenging. Herein, we demonstrate a novel and stable scintillator, achieved through a host–guest strategy involving the confinement of perovskite NCs, e.g., MAPbBr 3 NCs, in metal–organic frameworks (MOFs). The host MOF, bio-MOF-100 (denoted as bMOF), facilitates the in-situ space-confined formation of MAPbBr 3 NCs while providing quantum confinement, surface passivation, and protection to these guests. This host–guest strategy results in high exciton binding energy, bright and efficient luminescence, and significantly enhancing their stability against various factors such as air, heat, UV, solvents and X-ray irradiation. Consequently, this advancement prompts the transition of their application scenarios from the colloidal state to the solid state. The bMOF⊃MAPbBr 3 scintillator exhibits a linear response to X-ray with a detection limit determined to be 170 nGy air s−1. Moreover, the bMOF⊃MAPbBr 3 –PMMA scintillator screen demonstrates high-quality X-ray imaging with an impressive spatial resolution of 14.7 lp mm−1. This work provides a new avenue for the development of perovskite NCs-based host–guest composites and paves the way for the broader implementation in solid-state optoelectronic applications. [ABSTRACT FROM AUTHOR]

CsI(Tl) scintillator has been widely used in X-ray flat-panel detectors due to excellent performance characteristics including a suitable Si-photodiode emission wavelength, excellent optical output, and fast decay time. Here, a solution-based space-confined growth method was presented to achieve CsI(Tl) scintillator single-crystal flakes with controllable thickness. The grown CsI(Tl) single-crystal flake exhibits a comparable light yield (∼72,000 photons/MeV) and a lower afterglow level (0.1% @ 21 ms, 0.01% @ 118 ms) in comparison to that by the traditional melting method. This space-confined method allows for the achievement of a single crystal thickness of only 0.27 mm, making it suitable for direct application in X-ray detection and other related fields. It may open up new possibilities for the development of halide scintillator single crystals. A solution-based space-confined growth method enables the growth of high-quality CsI(Tl) single crystal flakes with controlled thickness for X-ray flat-panel detectors. [Display omitted] • A space-confined solution method is used to grown CsI(Tl) single-crystal flakes. • The thickness of the CsI(Tl) flake grown using this method can be controlled to be as thin as approximately 0.27 mm. • The CsI(Tl) flake exhibits a lower afterglow and a comparable light yield in comparison to that by the melting method. [ABSTRACT FROM AUTHOR]

As one of the commonly used scintillating materials, single crystals inhibit their further practical applications considering the high cost, limited volume, and time-wasting preparation technique. By the compelling requirement for radiative detection in a variety of fields, numerous novel scintillators have been developed. Here, a novel efficient and transparent Eu3+-doped boroaluminate glass was successfully fabricated by melt-quenching technique. The optical responses to ultraviolet–visible (UV) and X-ray are both significantly enhanced by heavily doping Eu3+ into the glass host. The optimal doping concentration of Eu3+ is 8 mol%. Moreover, the internal quantum yield (IQY) was evaluated to 53.2% with high transparency (83% @ 600 nm). More notably, the best specimen has 18.4% X-ray excited luminescence (XEL) integrated intensity of that of the commercial Bi 4 Ge 3 O 12 single crystal scintillator. According to our findings, heavily doped boroaluminate glass could be one of the alternative scintillating materials for slow process detection. [ABSTRACT FROM AUTHOR]

Thanks to the low melting point of hybrid glass, (ETP) 2 MnBr 4 namely, scintillators of arbitrary shapes were synthesized in a flexible silicon mold at low temperature (ca. 180 ℃), representing a new route to a transparent bulk of highly luminescence. [Display omitted] • The (ETP) 2 MnBr 4 glass was synthesized at a low temperature down to 180 ℃. • The luminescent glass exhibited a high transparency over 85% and a nearly-unity PL QY. • The internal crystallization of the hybrid glass was effectively driven by a mild annealing process at 60 ℃. • The low melting point of glass enabled the use of silicone molds for varied shapes, such as slide, monolith, and rod. • The ensuing scintillating screen for X-ray imaging achieved a high spatial resolution (26.8 lp/mm). In contrast to all-inorganic scintillators, organic–inorganic hybrid glass of low melting-point has many advantages in fabricating bulky and transparent scintillator at low temperature. Here, the (ETP) 2 MnBr 4 (ETPBr = ethyltriphenylphosphonium bromide) glass was successfully synthesized at 180 ℃, which exhibited a high transparency over 85 % (ranging from 500 to 800 nm) and a nearly-unity photoluminescence quantum yield. A mild annealing process at 60 ℃ was found effective to drive the interior crystallization of hybrid glass, which was only achievable at several hundred degrees for inorganic glass. The interior crystallization significantly improved the luminescence intensity at the expense of optical transparency. Importantly, based on the low melting point of (ETP) 2 MnBr 4 glass, flexible silicone molds were used as container to obtain a variety of scintillators of arbitrary sizes and shapes, such as alphabet, slide, monolith, and rod. The (ETP) 2 MnBr 4 glass was used as scintillating screen in X-ray detection and imaging, demonstrating a high light yield (66000 photons/MeV of annealed glass) and a high spatial resolution (26.8 lp/mm of transparent glass), respectively. This work not only refined the synthesis process of bulk scintillator, but also opened many avenues in luminescent volumetric display and three-dimensional imaging. [ABSTRACT FROM AUTHOR]

Scintillators have been commercialized as radiation detectors in several practical applications. However, fabrication of commercial inorganic crystal scintillators is time-consuming and expensive. Herein, we report inorganic glass scintillators for gamma and X-ray detection based on phosphate glasses, with alkali and alkali earth metals in the host and Ce3+ ions as emission centers. Unlike inorganic crystals, inorganic glasses have industrial advantages owing to their low cost and ease of fabrication, which facilitate the large-scale production of scintillators. Previously studied inorganic glass scintillators for gamma and X-ray detection exhibited low light yields compared to inorganic crystal scintillators. In contrast, our glass exhibits a high light yield of 3200 photons/MeV. This light yield is higher than that of previously reported glasses, whose light yields are less than several hundred photons/MeV in most cases and approximately 2000 photons/MeV as the highest value. In addition, this glass has a relatively high density of 3.33 g/cm3 and a fast scintillation decay of approximately 30 ns, which is attributed to the 5d–4f transition of Ce3+ ions acting as emission centers. These properties are suitable for gamma and X-ray detection and this glass has the potential to expand the practical applications of inorganic glass scintillators. • We fabricated a phosphate glass scintillator for gamma- and X-ray detection. • This glass exhibited a high light yield of 3200 photons/MeV. • This glass has the potential to expand applications of glass scintillators. [ABSTRACT FROM AUTHOR]

Ce3+ activated high-density lanthanum lutetium germanate glass was fabricated by melt quenching method. Their densities, fluorescence decay curves, transmittance spectra, and luminescence excited by UV light and X-ray were measured and investigated. The densities of the glasses are between 5.90 g/cm3 and 5.97 g/cm3. The glasses present blue emission upon 379 nm light and X-ray. The blue emission lifetimes of the glasses are between 11.26 ns and 18.83 ns. The results shows that Ce3+ activated high-density lanthanum lutetium germanate glass would be a potential fast-event X-ray detection scintillating material. • Ce3+ doped germanate glasses with density around 6 g/cm3 were prepared. • The glass showed blue emissions upon UV light and X-ray. • The blue emission lifetimes were in the range of 11.26–18.83 ns. [ABSTRACT FROM AUTHOR]

The urgent demand for radiation detection in diverse applications boosts extensive investigations on scintillators. However, the current scintillating materials are mostly limited to mono-crystals with high cost, restricted volume and time-consuming fabrication techniques. Here, we report an efficient and transparent Tb3+-doped Sr 2 GdF 7 glass ceramic (GC) prepared via simple melt-quenching method, and its optical response to X-ray. By incorporating Tb3+ into crystallized Sr 2 GdF 7 inside a typical aluminosilicate glasses, highly enhanced green emission was observed under UV and X-ray excitation. After thermal treatment, the internal and external photo-luminescence quantum yields can be as high as 59.1 and 26.4%, respectively, with the high transparency (65%@550 nm) preserved. More interestingly, this composite material, combining the advantages of oxide glasses and fluoride crystals, presents strong X-ray excited luminescence (XEL). Its XEL intensity is 194% of that of commercial BGO scintillator. Evidenced by detailed optical and structural properties, it can be concluded that rare earth ions activated bulk oxyfluoride glass ceramics with unique merits, such as low-cost, high efficiency and intense radio-luminescence, could be alternative scintillating materials for high energy ray detection. [ABSTRACT FROM AUTHOR]

Europium doped borosilicate glasses were prepared in CO reducing atmosphere. The glasses were systematically investigated through XPS, photoluminescence (PL), fluorescence decay curves and X-ray excited luminescence (XEL). XPS results show that the glasses contain Eu2+ and Eu3+ at the same time. Under the excitation of 360 nm light, only a broad blue emission with peak around 440 nm due to the 5d→4f transition of Eu2+ is observed, while the emissions from Eu3+ do not appear in the PL spectra. The fluorescence decay curves were monitored at 440 nm, and the measured lifetimes are in the range of 0.17–0.42 μs. The PL results indicate that the PL emission from Eu2+ is significantly intense than the PL emissions from Eu3+. Upon X-ray excitation, two main emissions with peaks at 445 nm and 616 nm corresponding to Eu2+ and Eu3+ are obtained. The XEL results reveal that the XEL emissions from Eu3+ are comparably intense as the XEL emission from Eu2+. The results indicate that europium doped borosilicate glass could be a potential scintillating material in X-ray detection filed. [ABSTRACT FROM AUTHOR]

State-of-the art X-ray imaging cameras using silicon sensors for X-ray detection have demonstrated a frame-rate of 10 MHz and excellent performance for X-ray energies below 20 keV. We proposed a pixelated ultrafast inorganic scintillator-based front imager for GHz hard X-ray imaging. The proposed imager is featured with a total absorption for hard X-ray photons, and provides sub-ns scintillation pulse width crucial for X-ray bunches of a few ns spacing foreseen at the proposed MaRIE facility. We measured temporal response of a dozen ultrafast and fast inorganic scintillators at the 10-ID-B site of the Advanced Photon Source (APS) of ANL. Crystal's response to hybrid X-ray beam of 30 keV, consisting of singlet bunches of 50 ps width and septuplet bunches of 27 ps width with 2.83 ns bunch spacing, was measured. Ultrafast inorganic scintillators, such as BaF 2 :Y and ZnO:Ga, show clearly resolved X-ray bunches for septuplets, as well as no degradation of amplitude for continuous eight septuplets, providing a proof of principle for the ultrafast inorganic scintillator-based total absorption front imager for the proposed MaRIE project. [ABSTRACT FROM AUTHOR]

The rising requirement for radiation detection materials for practical applications has inspired to burgeoning investigation of scintillator materials. High performance X-ray detection require high spatial resolution and long-term stability, particularly for targeted objects at extreme conditions. Here, the CaF 2 :Eu2+ glass ceramic (GC), in which the CaF 2 :Eu2+ nanoparticles are wrapped by the glassy matrix, is successfully obtained the melting method. The as-obtained CaF 2 :Eu2+ GC manifests bright blue radioluminescence (RL) emission peaked at 470 nm thanks to the effective 5d-4f transition of Eu2+ ions. In addition, the as-obtained CaF 2 :Eu2+ GC presents high transmittance of 84.2% and visible light, contributing an excellent spatial resolution of 15 lp/mm at room temperature. Importantly, the as-obtained CaF 2 :Eu2+ GC exhibits high robustness at water conditions and high thermal stability with X-ray resolution of 12.1 lp/mm at 473 K. Our work demonstrates that CaF 2 :Eu2+ GC scintillators provide an excellent visualization tool for high-resolution scintillators X-ray images in harsh conditions. • The reduction efficiency of Eu2+ is significantly improved by mixing the reducing agent with glass ceramic raw and sintering. • The CaF 2 :Eu2+ glass ceramic is successfully obtained by melt-quenching method. • Multiple characterization prove that Eu2+, the luminescent center of glass ceramic, is greatly reduced in glass ceramic. • The strategy significantly reduces the light scattering and enhance the stability of the emitting centers. • The CaF 2 :Eu2+ glass ceramic for high resolution X-ray detection in harsh conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Scintillator screen with micro/nano particles embedded into delignified wood. • Vertical column structured material suppressing the light lateral spreading. • Linear relationship between light yield and X-ray dose rate. • High spatial resolution X-ray imaging achieved. Nanocrystalline scintillators with low-cost, fast response, and high light yield are widely used for X-ray imaging. However, they fail in high-energy X-ray imaging because of the fundamental limitations due to lateral radiation spreading in thicker device-compatible active layers. This issue is resolved by using the novel nanocomposite containing CsPbBr 3 scintillation single-microcrystalites embedded into transparent, natural wood-derived light-guiding fibrous structures. The CsPbBr 3 crystals convert X-ray to visible photons with a high photoluminescence quantum efficiency (76 %), and an average fast photoluminescence decay time of 25.9 ns. The delignified wood-derived fiber-like lumina effectively guide light, while suppressing the lateral spreading of scintillation photons. This unique porous nanocomposite material offers an excellent X-ray detection performance, and linear response in a wide parameter range. The developed scintillator screen achieves well-resolved, high-contrast X-ray imaging, featuring a very high spatial resolution of 11.9 lp/mm at a modulation transfer function of 0.2, thus exceeding the benchmark industry standards and offering a new advanced materials platform for radiation detection and dosimetry applications. [ABSTRACT FROM AUTHOR]

Scintillators are used as radiation detectors because they absorb ionizing radiation and release energy as light. Inorganic glasses have significant advantages over inorganic crystals owing to their ease of fabrication, low cost, controllable shape, and thermal and chemical durability. However, large performance gaps, such as light yield and density, still exist between inorganic glasses and commercial inorganic crystals. Here, we present a demonstration of an inorganic scintillator based on phosphate glass with an alkali metal as the host and Ce3+ as the emission centers. This glass exhibits a high light yield of 2500 photons/MeV, which is higher than that of previously reported inorganic glass scintillators (approximately 2000 photons/MeV). The glass is transparent and has a fast decay time of approximately 30 ns, which is attributed to the 5d–4f optical transition of Ce3+, facilitating applications for inorganic glass scintillators for gamma- and X-ray detection. Furthermore, we investigated the difference in the energy-transfer efficiency of the fabricated inorganic glasses by changing the alkali metals. The energy transfer efficiency increases with an increase in the atomic number of the alkali metals; the thermoluminescence (TL) intensity decreases with an increase in the atomic number of the alkali metals. These results suggest that Cs is an optimum alkali metal to achieve a high light yield on phosphate glass scintillators, and they may be related to the difference in the number of electron–hole pairs that do not contribute to scintillation. • We fabricated a phosphate glass doped Ce3+ for gamma- and X-ray detection. • The fabricated glass scintillator exhibited a high light yield of 2500 photons/MeV. • Cs was an optimal alkali metal to achieve a high light yield. [ABSTRACT FROM AUTHOR]

A series of UVA-emitting LaB 3 O 6 :Ce3+ phosphors and La 0.96 Ce 0.04 B 3 O 6 /PMMA films were prepared. The calcining temperature, activator concentration and PL test temperature were studied for the luminescence properties of the phosphor. And the effect of phosphor content on transmittance and X-ray radiation capacity of the composite films was also studied. The results show that LaB 3 O 6 :Ce3+ emits continuous double peaks at 358 nm and 380 nm when excited at 333 nm, the fluorescence lifetime is about 10 ns, and the luminescence intensity at 150 °C is 73.71% of that at room temperature, which can be used as phosphors for UV phototherapy applications. Under X-ray excitation, the integrated intensity of the La 0.96 Ce 0.04 B 3 O 6 /PMMA composite film has a good linear relationship with the X-ray tube current and tube voltage, and the X-ray imaging of a car key taken by La 0.96 Ce 0.04 B 3 O 6 /PMMA composite film has good signal-to-noise ratio, which can be used for X-ray detection and imaging. • A UVA phosphor with good thermal stability can be applied to UV phototherapy. • LaB 3 O 6 :Ce3+ phosphor has no significant afterglow and can be used as scintillator material. • La 0.96 Ce 0.04 B 3 O 6 /PMMA composite film with good X-ray radiation capability can be used for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

Flexible and stretchable materials are increasingly being investigated for future technological platforms, polymer based materials being the most suitable candidates for those emerging technologies. This work reports on polymer based scintillator composites based on the thermoplastic elastomer Styrene-Ethylene/Butadiene-Styrene (SEBS) and Gd 2 O 3 :Eu 3+ scintillator nanoparticles, to form a polymer-based flexible and stretchable material for X-ray indirect detectors. Further, visible light yield under X-ray irradiation was improved by the inclusion of 2,5 dipheniloxazol (PPO) and (1,4-bis (2-(5-phenioxazolil))-benzol (POPOP) within the polymer matrix. Together with high levels of stretchability, with deformations up to 100%, the films exhibit suitable performance with low mechanical hysteresis (less than 1.5 MJ/m 3 for cycles up to 100% of strain) and reproducibly such as a scintillator material for the conversion of X-ray radiation into visible radiation. The decrease of just ∼13% of the X-ray radiation into visible light upon stretching up to 100% is attributed to a reduction of the effective filler concentration and proves the suitability of the developed materials for large area and stretchable X-ray radiation detectors. [ABSTRACT FROM AUTHOR]

In this paper, we present a multi-voltage threshold (MVT) digitizer using a time-varied threshold and investigate the feasibility of using this digitizer to develop the data acquisition system for photon-counting X-ray security inspection imaging. This digitizer compares the scintillation pulse with a preset time-varied voltage signal and records the time information of the intersections. As the amplitude of the threshold varies as a function of time, the voltage values of the intersections could be calculated using the recorded time, and the energy information could be extracted via the acquired time–voltage samples. Unlike the constant voltage thresholds MVT digitizer requiring multiple voltage comparators, this method needs only one voltage comparator, which notably reduces the complexity in configuration. We demonstrate the development of such an MVT digitizer using a sine signal threshold and evaluate its energy performance with a yttrium orthosilicate (YSO) scintillator and Silicon Photomultiplier (SiPM) detector (designed for X-ray detection). The digitizer obtains energy resolutions of 41.4%, 26.6%, and 25.5% at 30, 59.5, and 80.9 keV, respectively. For comparison, the YSO/SiPM detector is also evaluated with a high-speed oscilloscope, and measured energy resolutions are 40.6%, 26.5%, and 25.1% at 30, 59.5, and 80.9 keV, respectively. These results indicate that the proposed MVT digitizer using a time-varied threshold is a promising method for developing a YSO/SiPM-based photon-counting X-ray detector. [ABSTRACT FROM AUTHOR]

Developing efficient strategies to fabricate planar photoluminescence scintillators is of great importance to explore X-ray detectors with new platform. Rare-earth (RE) doped Lu 2 O 3 thin films are successfully fabricated by mild aqueous phase electrochemical deposition on ITO/glass substrates with low-temperature post-annealing treatment. The as-prepared Lu 2 O 3 :RE3+ (RE = Eu, Tb and Tm) thin films exhibit steerable thickness, high transparency in the visible-NIR range, and low transmittance at UV band mainly due to the oxygen-metal (O2--RE3+) charge transfer processes and the 4f-4f transitions of the RE3+. The Lu 2 O 3 :RE3+ thin films emit intense red, green and blue (RGB) photoluminescence, which mainly correspond to the 5D 0 -7F 2 transition of Eu3+, 5D 4 -7F 5 transition of Tb3+ and 1G 4 -3H 6 transition of Tm3+ respectively. Moreover, the transparent Lu 2 O 3 :RE3+ thin films also exhibit high sensitivity and linearity luminescence to the X-ray stimulation in a dose rate from 30 to 160 mGy s−1. This rapid and energy-saving synthesis show high efficiency to fabricate rare-earth doped thin-film with a tunable optical performance for optoelectrical application in the fields of solar light concentrators, agricultural light conversion thin films, biosensors, photodetectors and especially the X-ray detectors. [Display omitted] • The thickness of Lu 2 O 3 :RE3+ (RE = Eu, Tb and Tm) films prepared by electrodeposition is controllable. • The thin films exhibit high transparency at Visible-NIR band. • The Lu 2 O 3 :RE3+ thin films emit intense RGB photoluminescence upon UV light excitation. • The Lu 2 O 3 :RE3+ thin films exhibit high sensitivity and linearity to the X-ray. [ABSTRACT FROM AUTHOR]

The aims of this study is to improve the sensitivity of indirect X-ray detectors by investigating the properties and application of ternary-blended organic active layers. The ternary-blended active layers studied were composed of conjugated polymer PBDB-T-2F as the donor (D1), non-fullerene Y6 as the first acceptor (A1) and ITIC-4F as the second acceptor (A2). The structural similarity between the two acceptors allows the advantage formation of a homogeneous acceptor phase and results in good film morphology. Another advantage of our approach is the electrical and optical characteristics of the active layer can be modulated based on the mixing ratio of the two acceptors. To find the optimal ternary blending, the content of D1 was fixed while the A1:A2 content ratio was adjusted. The CsI (Tl) scintillator-coupled detector with an active layer of PBDB-T-2F:Y6:ITIC-4F = 1.0:0.6:0.4 achieved the highest sensitivity of 4.27 × 103 μC∙Gy air −1∙cm−2 giving respective improvements of 27.10% and 43.92% compared to binary-blend PBDB-T-2F:Y6 = 1:1 and PBDB-T-2F:ITIC-4F = 1:1. Next, the active layer's spin-coating conditions and the bias conditions were examined to further improve the sensitivity of the detector. Finally, the detector with a PBDB-T-2F:Y6:ITIC-4F = 1.0:0.6:0.4 active layer was shown to have the highest sensitivity of 5.42 × 103 μC∙Gy air −1 cm−2 at a bias of – 1.6 V with a 97 ± 2 nm thick active layer. The aims of this study are to improve the sensitivity of indirect X-ray detectors by investigating the properties of ternary-blended organic active layers. The structural similarity between the two acceptors allows the advantage formation of a homogeneous acceptor phase and results in good film morphology. Another advantage of our approach is the electrical and optical characteristics of the active layer can be modulated based on the mixing ratio of the two acceptors. The CsI (Tl) scintillator-coupled detector with ternary-blended active layer giving respective improvements of 27.10% and 43.92% compared to binary-blended active layer. [Display omitted] • To improve the sensitivity of the X-ray detector, a ternary-blend strategy was applied to the organic active layer. • The X-ray detector using ternary-blended active layer shown 27.10% and 43.92% higher sensitivity compared to their respective binary combinations (PBDB-T-2F:Y6 and PBDB-T-2F:ITIC-4F). • The indirect-type X-ray detector using PBDB-T-2F:Y6:ITIC-4F = 1.0:0.6:0.4 ternary-blended active layer was achieved a high sensitivity of 5.42 × 103 μC∙Gy air −1∙cm−2. [ABSTRACT FROM AUTHOR]

Single crystal of Tm-doped LaCl 3 (LaCl 3 :Tm3+) with the dimension of diameter 7 mm and length 55 mm was successfully grown using an in-house-developed Bridgman furnace. The grown crystal has the self-trapped exciton (STE) emission in the range of 300–500 nm along with the characteristic emissions corresponding to the 4f-4f transition of Tm3+ ions under X-ray excitation. The scintillation characterizations of the grown crystal were performed by pulse height spectra, scintillation decay time, as well as pulse shape discrimination studies under γ-ray and α-particle excitation sources. The LaCl 3 :Tm3+ crystal was found to have a high light yield (42,000 ± 4,200 ph/MeV) with 4.2% energy resolution under γ-rays excitation. Moreover, the pulse shape discrimination was studied using 137Cs and 241Am as the radiation sources with a good FOM value. The results conclude the LaCl 3 :Tm3+ single crystal to be a promising candidate for X-ray and γ-ray detection purposes. • The LaCl 3 :Tm3+ crystal was successfully grown by Bridgman technique. • Host STE band and characteristic Tm3+ transition are visible in the XIL studies. • High light yield (41,511 ± 2,906 ph/MeV) with 4.23% energy resolution (137Cs source). • The timing performance of crystal was found to be 3.42 μs (89%) with 137Cs source. • The excellent PSD capability of LaCl 3 :Tm3+ crystal between γ-ray and α-particles. [ABSTRACT FROM AUTHOR]

The glass formula of 20Li 2 O+10AlF 3 +2.5CaF 2 +(66.5- x)P 2 O 5 + x Gd 2 O 3 +1Eu 2 O 3 (PLACEu 1 Gd x), where x = 2,4,6,8,10 mol% have been prepared by conventional melt-quenching technique. These glasses' optical absorption, photoluminescence, decay time, and radioluminescence have been measured at room temperature. Judd-Ofelt's (J-O) analysis of PLACEu 1 Gd 8 has been investigated and the magnitude of parameters follows the trend as Ω 2 >Ω 4 >Ω 6. The important laser parameters such as radiative properties are calculated using J-O parameters and luminescence spectra. The decay time with the transition from the 5D 0 level was estimated under 274 nm and 394 nm excitation using bi-exponential fitting. CIE coordinates, CCT and intensity ratio have been calculated for glass samples. The integral scintillation efficiency of PLACEu 1 Gd 8 is 31% compared with BGO crystal. The PLACEu 1 Gd x glasses are promising for laser medium and x-rays detection material applications. • The effect of Gd 2 O 3 in Li 2 O–AlF 3 –CaF 2 –P 2 O 5 –Eu 2 O 3 glasses was investigated. • The phonon energy was approximate to be 1170.36 cm−1. • The quantum efficiency of PLACEu 1 Gd 8 glass is 97%. • The light yield of the prepared glass was estimated to be 31% of the commercial BGO crystal. • The calculation of CIE, CCT and intensity ratio of these glasses were shown reddish-orange emission. [ABSTRACT FROM AUTHOR]

We have investigated a hard X-ray detector system using a combination of a plastic scintillator and multi-pixel photon counters (MPPC). Photomultiplier tubes (PMTs) have typically been adopted to read scintillators because of their high gain and large photoelectric surface, and studies on PMT and scintillator systems are well advanced. However, PMTs have limitations; for example, they are relatively large in size, require high voltage to operate, and cannot be used in strong magnetic fields. On the other hand, MPPCs do not have such limitations and instead possess high quantum efficiency and a large compact size. Therefore, we have studied a detector system that combines an MPPC with a plastic scintillator. The system is primarily intended to be used for polarization measurements of high-energy astrophysical objects. We achieved an energy threshold of as low as ~5 keV while operating the detector at low temperature (−10 °C), reading the signal with short integration time (50 ns), and using a low-noise MPPC. We also confirmed that the light yield of our MPPC+plastic scintillator system is comparable to that obtained using a conventional PMT to read the scintillator signal. Herein, we report test results and future prospects. [ABSTRACT FROM AUTHOR]

To obtain both a high count rate of >10 7 s −1 and a detection efficiency sufficient for high-energy X-rays of >30 keV, we propose a scintillation timing detector using a proportional-mode silicon avalanche photodiode (Si-APD) for synchrotron radiation nuclear resonant scattering. We here present results obtained with a prototype detector using a lead-loaded plastic scintillator (EJ-256) mounted on a proportional-mode Si-APD (active area size: 3 mm in diameter). The detector was operated at ‒35 °C for a better signal-to-noise ratio. Using synchrotron X-rays of 67.41 keV, which is the same energy as the first excited level of 61 Ni, we successfully measured pulse-height and time spectra of the scintillation light. A good time resolution of 0.50±0.06 ns (full width at half-maximum) was obtained for 67.41 keV X-rays with a scintillator 3 mm in diameter and 2 mm thick. [ABSTRACT FROM AUTHOR]

Eu 3+ doped heavy germanate scintillating glasses were prepared by melt quenching method. Their physical and luminescent properties were investigated. The glasses exhibit the densities of more than 6.5 g/cm 3 . The transmittance spectra show the glasses have good transmittance in the visible region. The glasses show intense red emissions under 393 nm light excitation and X-ray excitation. The lifetimes of 614 nm emission of Eu 3+ -doped germanate glasses are in the range from 1.424 ms to 1.484 ms. The results indicate that Eu 3+ -doped high density germanate scintillating glasses could be of good anti-radiation properties and could be an X-ray scintillating material suitable to X-ray detection for slow event. [ABSTRACT FROM AUTHOR]

A new 1D coordination polymer [Pb(adba)(DMF)] n exhibits the competitive sensitivity, detection limit and radiation stability responsive to X-ray and could serve as a promising scintillating material candidate for X-ray detection in highly irradiating conditions. [Display omitted] • A new X-ray responsive 1D coordination polymer [Pb(adba)(DMF)] n (named as Pb-adba , H 2 adba = 4,4′-(9,10-anthracenediyl)dibenzoic acid, DMF = N , N -dimethylformamide) was constructed with Pb(II) salt and H 2 adba by a mild solvothermal process. • Pb-adba exhibits the competitive sensitivity and detection limit toward X-ray than classical scintillators PbWO 4 (PWO), anthracene and some reported SMOFs. • Pb-adba possess favorable radiation stability at the dose rate of 42.29 mGy/s for 3 h (equivalent to the cumulative dose of 456 Gy). The strong X-ray attenuation and beneficial optoelectronic properties of lead(II)-based coordination polymers (CPs) materials have aroused great interest in the field of radiation detection. In this work, a X-ray responsive scintillating 1D Pb(II)-CP [Pb(adba)(DMF)] n (named as Pb-adba , H 2 adba = 4,4′-(9,10-anthracenediyl)dibenzoic acid, DMF = N , N -dimethylformamide) with favourable irradiation stability was synthesized by the self-assembly approach, which exhibits competitive sensitivity and detection limit toward X-ray than classical scintillators PbWO 4 (PWO), anthracene and some reported SMOFs. [ABSTRACT FROM AUTHOR]

The scintillator film, as a key element affecting X-ray detection imaging resolution, has attracted more and more attention. At present, it is mainly obtained by grinding and polishing of crystal or ceramic scintillators and film evaporation technology, with high cost, limited size and long preparation period. In this work, we propose a simple method to prepare scintillator films by blending (Lu 0.995 Ce 0.005) 3 Al 5 O 12 nano-powders and polydimethylsiloxane (PDMS), and characterize the uniformity, light absorption, photoluminescence, and X-ray excited luminescence (XEL) of these. The XEL results show that the prepared LuAG:Ce-PDMS composite scintillator films have a clear broadband emission in the region of 480 and 680 nm, which can be well coupled with silicon photodiodes. Its XEL integral intensity is 286% that of commercial BGO scintillators, and the spatial resolution is 25 lp/mm when the film thickness is 100 μm. All of those show the LuAG:Ce-PDMS composite scintillator films have a potential application in scintillator-based indirect-type X-ray imaging. • A simple method to prepare scintillation films. • The XEL intensity of the film is 286% of that of commercial BGO scintillator. • The image resolution is 25 lp/mm when the film thickness is 100 μm. [ABSTRACT FROM AUTHOR]

A digital x-ray detector scheme based on a pixelated scintillator coupled with a fiber optic (FOT) array is suitable for many high-resolution x-ray imaging applications. However, certain challenges need to be addressed for fabrication of wafer-scale uniform pixelated x-ray scintillators. In addition, difficulties associated with implementation of the data acquisition system for acquiring output image data from the multiple image sensors used in the detector also need to be addressed. In this paper, a 2×2 FOT array-coupled digital x-ray detector scheme using a 5-in. pixelated scintillator is proposed. A novel fabrication setup along with the corresponding processes for fabricating the wafer-scale pixelated scintillator and implementation of a specially designed embedded data acquisition system based on a single embedded micro-processer (ARM) and four field-programmable gate array (FPGA) chips are discussed in detail. Preliminary experiments demonstrate that this pixelated scintillator-based digital x-ray detector scheme with an active imaging area of about 100 mm×100 mm shows considerable potential for use in high-resolution x-ray imaging. [ABSTRACT FROM AUTHOR]

The principle of the X-ray detector which can simultaneously perform the measurement of the exposure rate and 2D (two-dimensional) distribution is described. A commercially available CMOS image sensor has been adopted as the key part to receive X-ray without any scintillators. The correlation between the pixel value (PV) and the absorbed exposure rate of X-ray is studied using the improved Elman neural network. Comparing the optimal adjustment process of the BP (Back Propagation) neural network and the improved Elman neural network, the neural network parameters are selected based on the fitting curve and the error curve. The experiments using the practical production data show that the proposed method achieves high accurate predictions to 10 −15 , which is consistent with the anticipated value. It is proven that it is possible to detect the exposure rate using the X-ray detector with the improved Elman algorithm for its advantages of fast converges and smooth error curve. [ABSTRACT FROM AUTHOR]

Medical X-ray digital imaging systems such as mammography, radiography and computed tomography (CT), are composed from efficient radiation detectors, which can transform the X-rays to electron signal. Scintillators are materials that emit light when excited by X-rays and incorporated in X-ray medical imaging detectors. Columnar scintillator, like CsI:T1 is very often used for X-ray detection due to its higher performance. The columnar form limits the lateral spread of the optical photons to the scintillator output, thus it demonstrates superior spatial resolution compared to granular scintillators. The aim of this work is to provide an analytical model for calculating the MTF, the DQE and the emission efficiency of a columnar scintillator. The model parameters were validated against published Monte Carlo data. The model was able to predict the overall performance of CsI:Tl scintillators and suggested an optimum thickness of 300 μm for radiography applications. [ABSTRACT FROM AUTHOR]

To detect low-dose-rate X-rays, we have developed an X-ray-detecting module for semiconductor diodes. The module consists of a current–voltage ( I – V ) amplifier, a voltage–voltage ( V – V ) amplifier, and an alternating-current adopter with a smoothing circuit. The photocurrents flowing through a diode are converted into voltages and amplified using the I – V and V – V amplifiers. To measure relative sensitivities, we used three silicon PIN diodes (Si-PIN), a cerium-doped yttrium aluminum perovskite [YAP(Ce)] crystal, and a Lu 2 (SiO 4 )O [LSO] crystal. Three detectors are as follows: an Si-PIN, a YAP(Ce)–Si-PIN, and an LSO–Si-PIN. Using the three detectors, the amplifier output voltages were in proportion to the tube current at a constant tube voltage of 70 kV. Using a multichannel analyzer, the event-pulse-height spectra were measured to analyze X-ray-electric conversion effect in the three detectors. The output voltage of the Si-PIN was approximately twice as high as those obtained using the YAP(Ce)–Si-PIN and the LSO–Si-PIN at the measurement conditions. [ABSTRACT FROM AUTHOR]

Gd 2 O 2 S:Tb (P43) powder was widely used in soft X-ray detection due to its high light yield. Compared with P43, GAGG:Ce scintillator has high light transmittance, fast decay time and strong radiation resistance. Photonic crystals (PhCs) can be used to enhance the light output of scintillator. In this paper, two-dimensional (2D) photonic crystals that consist of square arrays of air holes etched into TiO 2 layer were fabricated on the exit surface of GAGG:Ce scintillator to enhance its light output. The luminescence spectra and the light output of GAGG:Ce scintillator with/without PhCs were measured at the BL08U1A beamline of Shanghai Synchrotron Radiation Facility. The results showed that the light output of GAGG:Ce scintillator with PhCs can be enhanced by a factor of 1.43 times compared with the reference GAGG:Ce scintillator, 2.35 times compared with YAG:Ce scintillator, 1.24 times compared with Gd 2 O 2 S:Tb scintillation ceramic and 0.76 times compared with P43 powder layer with the mass thickness of about 1.3mg/cm 2 with optical grease coupling. No significant change was observed in luminescence decay time between GAGG:Ce scintillator with and without PhCs. It makes GAGG:Ce scintillator with PhCs a promising material instead of P43 powder and YAG:Ce scintillator in soft X-ray detector. [ABSTRACT FROM AUTHOR]

Flexible Pb-MOF film serves as a scintillator screen for sensitive X-ray detection and high-resolution X-ray imaging. [Display omitted] • The Pb-MOF composite film is firstly used as the scintillating screen for X-ray imaging. • Lead-based metal–organic framework scintillator is prepared via the mild method. • Synergistic effect of inorganic and organic motifs in Pb-MOF is responsible for sensitive X-ray response. Scintillators that exhibit X-ray stimulated light response have attracted increasing attention for their wide application in medical diagnosis and treatment, security inspection, industrial flaw detection and other aspects. However, the broader application of traditional inorganic and organic scintillators has been limited by their high preparation cost or poor adaptability to changeable environments. Here, a scintillating 1D metal–organic framework (MOF) [Pb(adda)(DMF)] n 1 (H 2 adda = (2 E ,2′ E)-3,3′-(anthracene-9,10-diyl) diacrylic acid, DMF = N , N -dimethylformamide) was prepared by a low-cost and short-cycle solvothermal process. Benefiting from the intrinsic synergistic effect of functional motifs and robust architecture, sensitive and steady X-ray response signals of 1 are demonstrated with an excellent linearity to the X-ray dose rates and stable light output under 9 h per day continuous irradiation during five days. In addition, the flexible MOF-based scintillator film is firstly applied in X-ray imaging application, which achieves a relatively high spatial resolution of 5.5 lp mm−1. This work provides an effective visualization tool for X-ray radiography and verifies the potential application of flexible MOF-based scintillator film for X-ray imaging. [ABSTRACT FROM AUTHOR]

• Rb 2 CuBr 3 has low cost, high mass yield, high PLQY and suitable emission wavelength. • The materials have self-trapped excitons (STEs) for large stokes shift (90 nm). • Rb 2 CuBr 3 -PS composite screens films shown a sensitive response to X-ray signals. Environmentally stable, low cost, large stokes shift, adjustable area and flexibility are basic factors to prepare scintillator films for their commercial application. Here, a low cost (∼3 $/g) room-temperature ligand-assisted reprecipitation method is used to synthesize one-dimensional crystal structure based on Rb 2 CuX 3 (X = Br, Cl). Rb 2 CuBr 3 exhibits quite high mass yield of 90% with high Photoluminescence quantum yield (PLQY) of 59.06%. Importantly, its bright blue emission (90 nm stokes shift) is consistent with the highest optical detection efficiency wavelength range of commercial SiPM. Further characterizations point out that such effective blue emission comes from the recombination of excitons rather than the defects or combination of electron-hole pairs. And the existing strong exciton-photon coupling is conducive to the formation of self-trapped excitons (STEs). Finally, uniform and adjustable area Rb 2 CuBr 3 -polystyrene composite films have been successfully obtained. It's fascinating that the films exhibit ultra-flexibility (unchanged performance after multiple bending of 400 times) and excellent stability (subtle attenuation after 30 days of storage in a harsh environment). As an X-ray imaging screen, it presents a sensitive scintillation response to X-ray signals with superior linearity with high-quality images. Therefore, our prepared Rb 2 CuBr 3 scintillator shows great commercial prospects in the field of flexible X-ray detection. [ABSTRACT FROM AUTHOR]

Scintillator screens have been used on multiple devices for X-ray tomography, being responsible for conversion of the X-ray beam into visible light that is then focused to form an image. In this context, CdWO 4 -polystyrene composite films were tested as detector screens at the Imaging Beamline of the Brazilian Synchrotron Light Laboratory. Samples with varied thickness (150 μ m , 300 μ m and 600 μ m) and CdWO 4 load (10% and 40%) were characterized as a microtomography image screen. The performance of the composites as radiation sensors demonstrates the feasibility of using CdWO 4 -PS scintillator for digital imaging applications. Spatial inhomogeneities of the composites were corrected by a digital flat image, thus allowing successful acquisition of absorption coefficients of the projected reference. Photoluminescence emission spectra provided understanding of the role of CdWO 4 particles dispersion, which was optimized in order to reduce artifacts related to light scattering. In addition, spatial resolution of images acquired with CdWO 4 -PS was demonstrated to be improved with the higher scintillator concentrations and the smaller screen thickness. [ABSTRACT FROM AUTHOR]

A novel Eu3+ ions-based metal–organic coordination polymer with a peculiar "snake-shaped" chain structure has been synthesized, which exhibits efficient light emission, excellent line response to X-rays and high structure and luminescence stability against continuous irradiation. [Display omitted] • A new type of luminescent Eu-MOCP was synthesized by simple solvothermal method. • Synthesized Eu-based MOCP shows an efficient and stable light emission under X-ray excitation, and delivers an excellent linear response to X-ray dose. • Compound 1 demonstrates high structure and luminescence stability against continuous X-ray irradiation. In this paper, a novel Eu ions-based metal–organic coordination polymer (MOCP) named Eu(1,3,6,8-PTS)(H 2 O) 7 ·4H 2 OHbipy (1) (PTS = pyrenetetrasulfonic acid) has been prepared, and its structure, stability, photoluminescence and scintillation properties were systematically investigated. Compound 1 gives a peculiar "snake-shaped" chain structure with the aid of π-π stacking effect of 4,4′-bipyridine auxiliary template. An efficient and stable light emission was detected under X-ray irradiation, which presents an excellent linear response to X-ray dose. Moreover, this compound demonstrates high radiation stability, illustrating its potential as a scintillator for X-ray detection. This work not only provides guidance for the design and fabrication of sulfonic ligand derived MOCPs with Eu (III) ions coordiantion, but also demonstrates the potential of MOCPs scintillators for X-ray detection technology. [ABSTRACT FROM AUTHOR]

The capability of polycarbonate cladded ZnO nanowires as scintillating optical fibers, in the presence of the 10 keV X-ray is simulated using the Geant4 Monte Carlo simulation code. The simulated results show that using millions of scintillating fibers in a 1 mm 2 area, which are packed together in a polycarbonate membrane, have additional light guiding role that reduces the scattering of the X-ray generated optical photons inside the detector. This new low-cost technique can provide a higher spatial resolution X-ray imager with sharper edges at the object boundaries in comparison to a single crystal scintillating macro detectors. [ABSTRACT FROM AUTHOR]

Using a powder scintillator for a detection of gamma and X-rays allows to create detectors of various shapes, moreover the handling and fabrication of such scintillators is much easier than in the case of large or thin monocrystals. We report on the application of YAlO 3 :Ce powder to Mössbauer spectroscopy. The detection efficiency and the energy resolution of the scintillators made of powders of two different granularities (grain size ≤ 30 μ m and 50– 70 μ m) were investigated. The powder scintillators exhibited a comparable energy resolution and detection efficiency as YAlO 3 :Ce monocrystal with thickness of 400 μ m. Burying the YAlO 3 :Ce grains into the epoxy resin increased the energy resolution of powder scintillators. The studied scintillators were found to be suitable for experiments in Mössbauer spectroscopy. The performance of YAP is also compared to the NaI:Tl scintillator. [Display omitted] • Yap:Ce powder exhibits comparable detection efficiency as YAP:Ce monocrystal. • Covering YAP:Ce powder with epoxy resin increases its energy resolution and mechanical hardness. • YAP:Ce powder is efficient for a photon detection in Mössbauer spectroscopy. • Scintillation crystals of various shapes could be made from YAP:Ce powder. [ABSTRACT FROM AUTHOR]

A promising composite scintillator for used in ultrafast X-ray detection was successfully developed by compounding Cl-doped CuI phosphor with polystyrene (PS) (CuI:Cl-PS), and its crystal structure and luminescence characteristics were investigated in detail. The CuI:Cl-PS composite scintillator only exhibited an intense near-band-edge (NBE) luminescence with a decay time of sub-nanosecond, and the slow luminescence of CuI was entirely suppressed under the excitation of ultraviolet light or X-ray. Furthermore, the intensity of the ultrafast NEB emission for the composite scintillator was not basically deteriorated after storage in air at room temperature for six months. It is expected that the CuI:Cl-PS composite scintillator demonstrates a great potential application in ultrafast hard X-ray detection or imaging. • The CuI:Cl-polystyrene (CuI:Cl-PS) composite scintillator was successfully synthesized, and firstly proposed to use in ultrafast X-ray detection. • The CuI:Cl-PS scintillator has only an intense near-band-edge (NBE) emission under X-ray excitation. • The decay time of NBE emission for CuI:Cl-PS scintillator is up to sub-nanosecond, which is greatly significant for ultrafast X-ray detection. • The intensity of NBE for CuI:Cl-PS scintillator is not basically deteriorated after storage for 6 months in air. [ABSTRACT FROM AUTHOR]

In this study, a high-spatial-resolution scintillator-type X-ray detection system with a silicon separator was developed. The image characteristics are evaluated, and the approaches required for the practical application of the proposed system were discussed. X-ray inspection is an indispensable benefit in various fields; however, the spatial resolution of a scintillation-type X-ray detector is not as high as that of a direct-conversion X-ray imaging detector due to the scattering of the scintillator emissions. Therefore, the purpose of this study was to suppress such diffusion and improve the resolution to achieve a high-spatial-resolution scintillator-type X-ray imaging detector. Silicon wafers were processed to create small square holes in pixel patterns, and these holes were filled with the scintillator. The spatial resolution of the sample was then measured to confirm its improvement. The high-spatial-resolution of the scintillator-type detector was achieved using silicon separators. Moreover, appropriate noise characteristics and detection efficiency must be ensured to achieve good detection capability. Based on X-ray irradiation experiments and image quality evaluations, indicators were obtained for improving the image detection performance of the silicon separator in terms of noise and detection efficiency. Thus, the scintillator-type imaging detector with the high-spatial-resolution could be of practical use. • Spatial resolution of a scintillator-type X-ray image detector is improved. • Silicon wafer is processed to make small holes in a pixel pattern as a collimator. • Scintillator is separated by 400 μ m -thick silicon walls. • Significant results were obtained for scintillator-type imaging detectors. • Scintillation light intensity was successfully reduced by the silicon separator. [ABSTRACT FROM AUTHOR]

• Glasses in the system NaPO 3 -Ba(PO 3) 2 -MgF 2 -YF 3 doped with EuF 3 (x = 0.0-4.0 mol%) or Dy 2 O 3 (x = 0.0-1.0 mol%) were investigated as high energy sensors. • The glasses present excellent optical quality up to the dispersion level of 4.0 mol% Eu3+ and at least up to 1.0 mol% Dy3+. • No sign of photoluminescence or radioluminescence intensity saturation was observed for the highest RE activator concentration suggesting that higher RE activator concentrations could lead to still higher luminous output. • Photoluminescence spectra measured under varying excitation powers at 365 nm allow construction of calibration curves that can be used to quantitatively detect the UV radiation. • Luminescence and excited state lifetime values indicate the glasses are promising candidates for glass scintillators for X-ray detection. In this work, fluorophosphate glass samples with the composition 35NaPO 3 -30Ba(PO 3) 2 -25MgF 2 -(10- x)YF 3 –x[EuF 3 or Dy 2 O 3 ] with x = 0–4.0 mol% EuF 3 , or x = 0–1.0 mol% Dy 2 O 3 , were fabricated by the melt quenching technique. The glasses were characterized from the structural, thermal and optical-spectroscopic points of view. Emission spectra were measured in the visible range upon UV excitation. Luminescence decay curves were registered by monitoring the most intense emissions of Eu3+ (5D 0 →7F 2) and of Dy3+ (4F 9/2 →6H 13/2) in the red and green, respectively, and from them the average lifetime values of the excited states 5D 0 of Eu3+ (2.5 ms) and 4F 9/2 of Dy3+ (0.71 ms) were determined. Emission spectra measured under variable excitation power yielded calibration curves for Eu3+ and Dy3+-doped glasses. The response to X-ray excitation was evaluated through radioluminescence measurements. The results indicate the promising application of these glasses in scintillators and for X-ray sensing devices. [ABSTRACT FROM AUTHOR]

• Laser chemical vapor deposition can significantly increase deposition rates. • The use of sapphire substrate helps to reduce thermal stress. • Micro-columnar film achieves high spatial resolution without reducing thickness. • The film in synchrotron radiation X-ray detection shows sub-micrometer resolution. Lu 2 O 3 :Eu scintillation film is one of the most attractive candidate for the hard X-ray imaging, especially for sub-micrometer spatial resolution X-ray detectors. This study was focused on the preparation and characterization of Lu 2 O 3 :Eu structured scintillation film on (0 0 1) sapphire substrate by laser chemical vapor deposition (LCVD). The grazing incidence X-ray diffraction (GIXRD) measurement shows that the film with thicknesses of 3 μm is oriented along the (4 1 1) direction. The morphology and luminescent properties, including photoluminescence excitation (PLE), photoluminescence (PL) and PL decay, were measured and discussed. The sub-micrometer spatial resolution was obtained at BL13W1 station at Shanghai synchrotron radiation facility (SSRF). [ABSTRACT FROM AUTHOR]

Bi-loaded plastic scintillators were successfully synthesized using the solvent evaporation method and were used as detectors for synchrotron X-ray radiation. The photoluminescence emission spectra and X-ray-excited radioluminescence spectra of all prepared plastic scintillators presented broad emission bands in the range of 350–500 nm, which derived from the fluorescence of the organic phosphor, 2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole. The detection efficiency of 1 mm thick plastic scintillators for high-energy X-ray photons was increased by the addition of Bi compounds (up to 2.3 wt%) and reached 67% of that of EJ-256, the commercially available Pb 5 wt% loaded plastic scintillator. Subnanosecond time resolution was successfully achieved for all scintillators. • Bi-loaded plastic scintillators were successfully fabricated. • Bi-loading increased detection efficiency up to 1.35 times. • Time resolution dependence on concentration of Bi was insignificant and ranged from 0.49 to 0.63 ns. [ABSTRACT FROM AUTHOR]