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• Liquid epitaxy boosts δ-CsPbI 3 's one-dimensional growth, enhancing carrier transition. • Sensitivity reaches 1768.46 μC Gy air -1 cm−2 at 432 V mm−1, outperforming α-Se and single crystalline δ-CsPbI 3 detectors. • Retains 91.34 % sensitivity after 7 days in air, showcasing impressive long-term stability. • Successful integration with a thin-film transistor array for 8-bit imaging in a 64 × 64 matrix. • Opens the door for commercial high-performance direct X-ray detectors, solving the "absorption vs. transportation" issue. An ideal direct X-ray detector should convert a low dose of X-ray photons into large quantity of electrical signals, coupled with sustained long-term stability. Nevertheless, a notable conflict arises between X-ray absorption efficiency and carrier transport in thick polycrystalline perovskite films. Moreover, conventional perovskite materials exhibit inherent challenges regarding the stability of their crystal phase and the consistency of the photocurrent. To circumvent these limitations, a polycrystalline perovskite thick film is proposed using orthorhombic CsPbI 3 (δ-CsPbI 3) as a highly stable active material. Combined with the liquid epitaxy process, δ-CsPbI 3 prefers one-dimensional growth along the carrier transportation direction, which suppresses the formation of grain boundaries, enabling high carrier mobility while maintaining X-ray absorption for a thick polycrystalline film. Consequently, the polycrystalline δ-CsPbI 3 based detector exhibits a highest sensitivity of 1768.46 μC Gy air -1 cm−2 at an electric field of 432 V mm−1 which is 88.42-fold higher than α-Se based detectors and 190-fold higher than the single crystalline δ-CsPbI 3 based detector, respectively. The sensitivity maintains 91.34 % of its initial state after 7 days exposure in the air. Combing with a thin-film transistor array, the detector achieves 8-bit imaging within a 64 × 64 matrix. This work provides a feasible method for commercialized production of high-performance direct X-ray detectors. [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]

[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]

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]

[Display omitted] • BN nanosheets act as a barrier, inhibiting ion migration within perovskite layers. • BN also improved charge transport and carrier mobility. • Perovskite photodiodes incorporated with BN exhibit exceptional X-ray stability. Metal halide perovskites have been widely used in optoelectronic applications due to their excellent optoelectronic properties. However, ensuring their stability during operation remains a significant challenge. In this study, we investigated the charge carrier dynamics of perovskite films and devices, comparing those with and without the insertion of boron nitride on the grain boundaries. It was revealed that the charge transport and stability could be significantly enhanced with the present of boron nitride nanosheets on the grain boundaries. The incorporation of boron nitride led to a substantial improvement in charge carrier mobility and lifetime, without any noticeable changes in phase segregation or photostability. Moreover, the perovskite detectors incorporating boron nitride exhibited suppressed ion migration and dark current, while demonstrating an enhanced photoresponse and radiation exposure capability. These findings indicate that the addition of insulating boron nitride nanosheets acts as a stabilizer, enhancing the stability of both the perovskite thin films and the devices. Additionally, the incorporation of boron nitride significantly improved the device performance benefiting from the enhanced charge transport, indicating that the boron nitride nanosheets enhanced perovskite photodiodes possess great potential for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

[Display omitted] CsPbBr 3 -CsPb 2 Br 5 wafer is obtained by water-assisted coprecipitation method, and a spray-coating method is further utilized to convert it into CsPbBr 3 -CsPb 2 Br 5 -CsPbI x Br 3-x composite wafer, which exhibits superior performance and reliability of X-ray detection. • Water-assisted coprecipitation is proposed to prepare high-quality CsPbBr 3 -CsPb 2 Br 5 powder. • CsPbBr 3 -CsPb 2 Br 5 wafer is obtained by pressure-induced aggregation of the powder. • Spray-coating of CsI/H 2 O onto CsPbBr 3 -CsPb 2 Br 5 wafer can convert it into CsPbBr 3 -CsPb 2 Br 5 -CsPbI x Br 3-x composite wafer. • X-ray detector with the composite wafer exhibits much improved performance and reliability. Lead halide perovskite wafers with large lateral size, controllable thickness, and desirable optoelectronic characteristics are promising for X-ray detectors. Herein, CsPbBr 3 -CsPb 2 Br 5 -CsPbI x Br 3-x composite wafers are prepared via water-assisted coprecipitation and spray coating. The preparation involved pressure-induced aggregation of the CsPbBr 3 -CsPb 2 Br 5 powder produced through coprecipitation using of H 2 O/MeOH mixed solvent into CsPbBr 3 -CsPb 2 Br 5 wafers, followed by spraying a CsI/H 2 O solution onto the wafer surface to transform it into a CsPbBr 3 -CsPb 2 Br 5 -CsPbI x Br 3-x composite wafer. Multiple favorable properties, including compact surface, high crystallinity, excellent carrier transportation, large/adjustable size, low cost, and mass producibility, can be identified for the CsPbBr 3 -CsPb 2 Br 5 -CsPbI x Br 3-x composite wafer. An X-ray detector with high performance and excellent stability is realized with this wafer. It yields high resistivity (ρ; 1.3 × 109 Ω cm−2, exceptional carrier mobility (μ)/lifetime (τ) (μτ) product (1.01 × 10−3 cm2 V−1), high sensitivity (20555.1 μC Gy air −1 cm−2), and low detection limit (127.7 nGy s−1). Hence, our research provides a reliable strategy for optimizing the structure and performance of perovskite wafer-based X-ray detectors and enabling mass preparation. [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]

[Display omitted] • Two semiconductive Ba(II)-based CPs 1 and 2 with small exciton binding energy (E b) values were successfully prepared. • The 2 -based film detector achieves superior direct X-ray detection performance among CP-based detectors. • The enhanced π-π interactions are beneficial to exciton separation and charge carrier transport irradiated by X-ray. High-performance and low-cost X-ray detector is crucial for medical imaging, nondestructive industrial detection and security checks. Semiconductive coordination polymers (CPs) with designable structures, tunable property and high cost-effectiveness have recently emerged as promising materials in direct X-ray detection. However, due to the strong Coulomb interactions between photogenerated electrons and holes, most of CPs often exhibit high exciton binding energies, resulting in relatively insufficient exciton dissociation as well as low photocurrent output and detection sensitivity in turn. Here, we employed the anthracene-based ligand to obtain two semiconductive CPs, {[Ba 2 (Hadba) 4 (DMF) 8 ]·DMF} n 1 (H 2 adba = 4,4′-(9,10-anthracenediyl)dibenzoic acid, DMF = N , N -dimethylformamide) and [Ba(Hadba) 2 (DMA) 4 ] n 2 (DMA = N , N -dimethylacetamide). Both of them can effectively convert X-ray into electrical signals. Compared with compound 1 , compound 2 has a reduced E b (44.9 meV) caused by the reinforced π-π interactions, contributing to the facilitated carrier transport, a significant enhance in mobility-lifetime product (μτ) and detection sensitivity irradiated by X-ray. Based on the optimized detection performance, we prepared a flexible 2 -based composite film detector with a low detection of 1.02 μGy/s that meets the standard for medical imaging. In particular, this film-based detector achieves a high sensitivity of 137.31 μCGy−1 cm−2 and μτ product of 3.03 × 10−3 cm2 V−1, which are superior to all previously reported CP-based detectors and much higher than commercial α -Se. Simultaneously, a 5 × 5 pixelated X-ray imaging device was further constructed to show its potential application in direct X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

• X-ray-responsive PNIPAm-based microgels are obtained. • Diselenide/ditelluride crosslinkers are synthesized. • PNIPAm microgel-based interferometers are generated. • Interferometers can respond to 0–50 Gy X-rays with tunable colors. • Interferometers show ultrahigh sensitivity of 101.63 nm/Gy. We report the successful development of novel microgel-based interferometers for X-ray dose sensing, which can meet fast-developing and widespread applications of ionizing radiation. Poly(N-isopropylacrylamide) (pNIPAm)-based microgels are crosslinked by different molecules (i.e., N, N'-methylenebisacrylamide (BIS), N, N'-bis(acryloyl)cystamine (BAC), bis(2-acrylamidoethyl) diselenide (BASe), and bis(2-acrylamidoethyl) ditelluride) (BATe). These color-tunable photonic materials are generated by sandwiching X-ray-responsive microgels between two Au layers. The radiolysis of an aqueous solution by X-ray irradiation yields •OH radicals, leading to the cleavage of crosslinkers of pNIPAm-based microgels. The chemical reaction induces the swelling of microgels, increasing the distance between the two Au layers of the interferometers. Eventually, the optical signal of the device (i.e., reflectance spectra and color) varies with the X-ray dose, showing an ultrahigh sensitivity of 101.63 nm/Gy. For the first time, our work provides novel microgel-based interferometers for spectral and visual X-ray dose detection via the chemical–mechanical-optical signal transduction strategy. [ABSTRACT FROM AUTHOR]

AgI incorporated perovskite X-ray detectors were fabricated based on the spray-coating technique. The effect of AgI incorporation on the optoelectronic properties was systematically investigated. With suitable amount of AgI content, metal halide perovskite exhibited improved crystallinity, charge carrier mobility, lifetime, and X-ray sensitivity. [Display omitted] • Perovskite thick films were fabricated via spray-coating process. • The effect of AgI incorporation was carefully evaluated and optimized. • X-ray detectors based on the spray-coated perovskite thick junctions were fabricated. • High X-ray sensitivity, low detection limit and fast response were achieved. Metal halide perovskites have emerged as a promising candidate for ionizing radiation detection, thanks to the facile fabrication, excellent optoelectronic properties and high attenuation coefficient. In order to fully absorb the incident X-ray photons, X-ray detectors require relatively thick active layers. However, it is challenging to obtain thick perovskite films based on conventional solution-based techniques, due to the limited solubility and viscosity of the perovskite precursors. In this work, we introduced spray-coating to deposit perovskite films on various substrates, and achieved tunable and thick films. On the other hand, the charge transport is another issue limiting the device performance of perovskite X-ray detectors. Compared with conventional inorganic semiconductors, hybrid perovskites possess relatively poor charge carrier mobility and lifetime. To address this issue, we incorporate AgI within the perovskite precursor, and systematically investigated their optoelectronic properties. It was found that the optimized AgI incorporated perovskite films exhibited the highest mobility-lifetime product, resulted X-ray sensitivity up to 3433 μGy air −1 cm−2 and ultra-low detection limit of 3.5 nGy air s−1, suggesting great potential for X-ray detection. [ABSTRACT FROM AUTHOR]

This work puts forward the idea of dual-mode X-ray detection using color change and electric signal, and provides a MOF (metal–organic framework)-based host–guest strategy to synthesize rewritable radiochromic semiconductive materials, which are promising to avoid the lack of digital processing ability and reusability of commercial radiographic/radiochromic films and the non-portability of commercial electric detectors. [Display omitted] • Obtain the first rewritable radiochromic semiconductor via a host–guest strategy. • Realize X-ray detection using color change and electric signal for the first time. • Exhibit color change and electric signal upon irradiation in the REVERSIBLE mode. • Achieve a sensitivity of 3216 µCGy–1cm−2, higher than known MOF-based detectors. This work puts forward the idea of dual-mode X-ray detection using color change and electric signal, and provides a MOF (metal–organic framework)-based host–guest strategy to synthesize rewritable radiochromic semiconductive materials, which are promising to avoid the lack of digital processing ability and reusability of commercial radiographic/radiochromic films and the non-portability of commercial electric detectors. The obtained semiconductor with photochromism-active viologen exhibited rapid color change from colorless to blue and photocurrent response upon irradiation of X-ray and was easily bleached after thermal annealing for reuse. As an application example, the inner detail of a printed circuit board was successfully revealed through radiochromic imaging. Meanwhile, a single-crystal detector of the semiconductor achieved a sensitivity of 3216 µCGy–1cm−2, which is higher than those of all reported MOF-based detectors and commercial α-Se detectors. [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]

• CoFe 2 O 4 -rGO composites were successfully synthesized by a hydrothermal method. • OFX and CFZ were degraded by radical and non-radical based oxidation, respectively. • rGO acts as a platform and electron bridge rather than an actual catalyst. • DFT calculations enabled degradation pathways for CFZ and OFX to be proposed. In this work, reduced graphene oxide (rGO) sheets were integrated with CoFe 2 O 4 to construct distinctive composites that were evaluated as heterogeneous catalysts activating peroxymonosulfate (PMS) for the oxidative degradation of ofloxacin (OFX) and cefazolin (CFZ), two widely used pharmaceuticals belonging to the fluoroquinolone and β-lactam antibiotic families, respectively. The results showed that of all of the catalysts tested, the composite with an CoFe 2 O 4 to rGO weight ratio of 20:2 (CFGO202) had the best reactivity, and achieved superior stability with negligible leaching of cobalt and iron under mild acidic conditions. Radical quenching experiments showed that the degradation of OFX was a radical-based oxidation process, while the decomposition and transformation of CFZ were largely due to PMS-induced direct oxidation via direct two-electron transfer. The near-complete degradation of OFX and CFZ could be attained under optimal conditions: pH 6.0, 0.1 g L−1 CFGO202 and 1 mM (for OFX) or 100 μM PMS (for CFZ). In comparison with OFX, the degradation of CFZ suffered less interference from the water matrix. An underlying mechanism was proposed based on the detection of radicals and X-ray photoelectron spectroscopy spectral data. Degradation intermediates were identified and the possible degradation pathways were proposed with the aid of density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]