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Vacuum‐evaporated metal halides (MHs) scintillator thick films have received much attention in the X‐ray imaging field due to their excellent light yield and uniform large‐area preparation. However, the inevitable heteromorphic homologs in MHs (e.g., Copper‐based MHs (Cu‐MHs): CsCu2X3∖Cs3Cu2X5) and change of film structural backbone will result in spectral hybridization (phase purity), and the film eventually detaches (lattice mismatches). Herein, a single‐source vacuum evaporation method to prepare a thick film (≈10 µm) of Cu‐MHs (as an example) scintillators is realized: 1) Presynthesis of pure phase materials by solution method with a protective agent to ensure phase purity without precise control of component ratios in evaporation process; 2) One‐shot formation of film structural backbone avoids stress accumulation and utilize the longitudinal growth characteristics of crystalline films to obtain crystal orientations with better optical outputs. Finally, the films obtained have a light yield comparable to a partially single‐crystal (53 983 photons MeV−1) and an imaging resolution (14.1 lp mm−1) comparable to the partial template method. The detection system based on the prepared Cu‐MHs scintillator thick films exhibits good response speed and linearity in response to different X‐ray radiation intensities and exposure times. The method will further drive the application of MHs is believed. [ABSTRACT FROM AUTHOR]

0D organic metal halide hybrids (OMHHs) have recently emerged as a new generation of scintillation materials, due to their high luminescence quantum efficiency, sensitivity, stability, and cost‐effectiveness. While numerous 0D OMHH scintillators have been developed to date, most of them are based on solution grown single crystals that require time‐consuming synthesis and are limited in size. Here, high‐performance X‐ray scintillators based on facile solution processed 0D OMHH amorphous films are reported for the first time. By reacting triphenyl(9‐phenyl‐9H‐carbazol‐3‐yl) phosphonium bromide (TPPcarzBr) with manganese bromide (MnBr2), 0D (TPPcarz)₂MnBr₄ amorphous films can be prepared via solution processing with mild thermal annealing, which exhibits green photoluminescence with an emission maximum ≈517 nm and a photoluminescence quantum efficiency of ≈87%. The X‐ray scintillation of 0D (TPPcarz)₂MnBr₄ amorphous films is characterized to exhibit a light yield of 44600 photon MeV−1 and an outstanding linearity with a low limit of detection of 32.42 nGyairs−1 over a wide range of X‐ray dose rates. The versatile processability of 0D (TPPcarz)₂MnBr₄ is illustrated with remarkable recyclability, high cost‐effectiveness, and scalability for large‐scale production. By taking advantage of the amorphous nature of newly designed OMHHs, the approach opens up new opportunities for developing high‐performance, solution‐processable scintillators. [ABSTRACT FROM AUTHOR]

Inorganic scintillators play a pivotal role in diverse fields like medical imaging, nondestructive detection, homeland security, and high‐energy physics. However, traditional inorganic scintillators encounter challenges such as high fabrication costs and low light yield. Recently, low‐dimensional metal halide scintillators (LDMHS) have witnessed rapid progress, owing to their distinctive crystal structure and superior radioluminescence performance. Herein, an overview of recent advancements and proposed instructive pathways for achieving high‐performance LDMHS is provided. First, the scintillation physical mechanism and emphasis on the essential requirements of scintillators for diverse applications are elucidated. Furthermore, LDMHS are classified according to B‐site cations, and their respective characteristics and recent advancements are introduced. This encompasses the understanding of structure‐property relationships and the routes and rules for optimizing scintillation performance. Finally, the persisting challenges in this burgeoning field and proposed potential research directions for future exploration are discussed. [ABSTRACT FROM AUTHOR]

Lead halide perovskite nanocrystals (LHP‐NCs) incorporated within polymer matrices have emerged as promising materials for various photonic applications. However, challenges persist in achieving high‐quality nanocomposites due to low monomer conversion yields, restricted LHP‐NCs loadings, and difficulty in maintaining NCs integrity post‐polymerization. A novel protocol for synthesizing LHP‐NCs/poly(methyl methacrylate) nanocomposites in a single step via the NC‐initiated photoinduced electron transfer‐reversible addition‐fragmentation chain transfer (PET‐RAFT) method is presented. Polymerization initiation mediated by NCs surfaces under blue light enables the fabrication of homogeneous nanocomposites with NCs loadings up to 7% w/w and ≈90% monomer conversion even in the presence of oxygen. This process preserves the optical quality of the NCs and passivates NCs surface defects, resulting in nanocomposites exhibiting near unity luminescence efficiencies. The potential of this approach for producing highly loaded nanocomposites for radiation detection is validated by radioluminescence measurements showing light yield values of 6000 ph MeV−1 and fast scintillation dynamics with effective lifetime of 490 ps, showing promise for time‐of‐flight radiometry. [ABSTRACT FROM AUTHOR]

The sensitive and rapid detection of thermal neutrons holds significant importance in various fields such as energy utilization, medical treatment, and national defense. However, the available thermal neutron scintillator is difficult to reach this target, mainly limited by the optical and scintillating performance. Herein, the in situ crystallization strategy of glass to construct scintillation glass composites for efficient thermal neutron detection is proposed. The congruent crystallization of the hybridized alkali earth silicate glass system may not only achieve high crystallinity, but also will keep the refractive indexing matching between the precipitated crystal and precursor glass phases. The prepared glass composites feature high luminescence efficiency, optical transmission and excellent neutron response properties. These factors collectively contribute to the robust neutron scintillation performance with a light output of ≈36 000 photons/neutron, which represents the highest value among glass‐based scintillators. Moreover, the composite configuration brings about the additional function of thermal neutron and γ‐ray discrimination. By using this composite scintillator, the neutron detector is constructed and demonstrates its application for detecting thermal neutron and distinguishing it from γ‐ray in an online way. The studies prove that glass composites with high crystallinity are expected to be promising candidates for a new generation of multifunctional neutron detectors. [ABSTRACT FROM AUTHOR]

Scintillators can convert the ionizing radiation into visible light and are crucial in X/γ‐ray detectors. Commercial detectors often use multiple scintillators with photodetector arrays, where optical crosstalk can degrade the performance. Chiral scintillators, emitting circularly polarized light, offer a promising solution for regulating the direction of light propagation to enhance X‐ray detecting merits. Here novel chiral metal‐organic polymers have been developed via photopolymerization, using chiral polymeric monomers and 0D Mn(II)‐based organic‐metal halide hybrid scintillators, achieving luminescence dissymmetry factors (glum) of 5.823 × 10−2 and −2.877 × 10−2. Two such scintillators, (atpp)2MnCl4·0.5H2O (MnCl4−1) and (atpp)2MnBr4 (MnBr4−2), exhibit excellent X‐ray scintillation rooted in tetrahedral [MnX4]2− crystal field. Compound MnBr4−2, with heavier bromine atoms, shows superior performance with a detection limit of 0.117 µGyair s−1, compared to 0.330 µGyair s−1 of MnCl4−1, both surpassing the medical diagnostic standard of 5.50 µGyair s−1. The chiral metal‐organic polymer film derived from MnBr4−2 has achieved a resolution up to 14.84 lp mm−1, exceeding medical standards for dental (2.0 lp mm−1) and breast cancer (10.0 lp mm−1) imaging. These advancements in chiral scintillators hold significant promise for high‐resolution X‐ray medical imaging applications. [ABSTRACT FROM AUTHOR]

Organic thermally activated delayed fluorescent (TADF) scintillators hold promising potential for applications in medical radiography and security detection, but the poor X‐ray absorption ability and inferior radioluminescence (RL) hampered their progression. Herein, the study has pioneered the development of high‐performance TADF Ag(I)‐based scintillators from M2X2(dppb)2 (M = Ag, Cu; X = Cl, Br, I) complexes with 1,2‐Bis(diphenylphosphino)benzene (dppb) ligand. In comparison with Cu(I) complexes, the Ag(I) series generally exhibited superior scintillation performance. Notably, Ag2Cl2(dppb)2 (Ag1) stands out with exceptionally high RL intensity (≈125% higher than that of CsI:Tl) and a low detection limit of 59.8 nGy s−1. The outstanding scintillation performance of Ag1 is primarily attributed to the synergistic effect of the high exciton utilization efficiency origin from a small singlet‐triplet energy gap, enhanced X‐ray absorption capacity by heavy atoms, and the high photoluminescence quantum yield (76.47% in ambient atmosphere). By fabricating a flexible film constructed with Ag1 submicron crystalline powders, a high spatial resolution of 25.0 lp mm−1 for X‐ray imaging is obtained. It offers new opportunities for utilizing TADF metal–organic complexes for highly efficient X‐ray scintillation and imaging. [ABSTRACT FROM AUTHOR]

Copper halides, a new class of attractive and potential scintillators, have attracted tremendous attention in X‐ray imaging. However, the ambiguity surrounding their exciton properties and the unclear effect of crystal structure on their photophysical performance hinder an in‐depth understanding of their luminescence mechanism and their further application in the X‐ray imaging field. Herein, copper halide scintillators Cs3Cu2X5 (X = I, Br, and Cl) with a 0D crystal structure is prepared, and their photophysical properties and luminescence mechanism are revealed using both theoretical calculation and experimental verification. The small exciton Bohr diameter together with the high exciton binding energy can cause Cs3Cu2X5 to hold strongly confined excitons and lack quantum‐size effects. The 0D Cs3Cu2X5 materials exhibit a structural framework with a soft crystal lattice and Frenkel excitons with strong confinement effects, further resulting in a luminescence mechanism with self‐trapped excitons. In particular, Cs3Cu2I5 is demonstrated as an efficient scintillator with high radioluminescence efficiency and high spatial resolution of ≈106 µm in radiography, which is primarily attributed to strongly confined excitons to improve the radiative recombination probability of electron‐hole pairs. Overall, this work provides a pathway for developing 0D scintillators with strongly confined excitons to improve X‐ray imaging performance. [ABSTRACT FROM AUTHOR]

Low‐dimensional organic–inorganic metal halides (OIMHs) have emerged as promising light emitters due to their broadband emission originating from self‐trapped excitons (STE), especially for Cu‐based OIMHs. Herein, Cu(I)‐based OIMH with a structure of (TPP)2Cu4I6·2DMSO (TPP stays for tetraphenylphosphonium, and DMSO – for dimethyl sulfoxide) has been synthesized, both in form of single crystals and as a microcrystalline powder. This compound exhibits a broadband green emission with a peak at 515 nm and a full width at half‐maximum of 78 nm, and a near‐unity photoluminescence quantum yield of 99.5%. Experimental data supported by theoretical calculations indicate that the STE emission is responsible for the green emission with a long lifetime of 2.53 µs. Down‐conversion light‐emitting device with a high luminous efficiency of 50 lm W−1 based on this compound have been fabricated, and white light has also been achieved with a high color rendering index of 96.7. Moreover, green emissive (TPP)2Cu4I6·2DMSO is utilized in scintillators for X‐ray detection and imaging, and as a luminescent ink for encryption applications. [ABSTRACT FROM AUTHOR]

Broadband emissive perovskites are next‐generation materials for solid‐state lighting and radiative detection. However, white‐emitting perovskites are generally synthesized by regulating B/X sites, while not enough attention is paid to the A‐site, which is thought to hardly affect the band‐edge structures and optoelectronic properties. Here, a series of Sb3+‐doped In‐based 0D halide perovskite derivatives are described with various organoammonium cations in A‐sites. Warm‐white light emitting across the visible spectrum (450–850 nm), large Stokes shifts, and high photoluminescence quantum yields are easily tunable by molecularly tailoring A‐site cations. These features enable a light yield up to 60976 Photons/MeV as X‐ray scintillator, and a detection limit of 90 nGyair/s that is ≈60 times lower than the medical requirement. It is proved that A‐site plays a critical role in determining the degree of distortion of polyhedra, which influences the broadband photoluminescence and self‐trapped exciton (STE) dominates the emission process. Moreover, for the first time, via the incorporation of 2,6‐dimethylpiperazine, a mixed A‐site regulating strategy produces a standard white‐light emission, which originates from the blue‐light and yellow‐light related to various STE emission centers. It is foreseen that this strategy highlights the expanded role of A‐site and the importance of rethinking A‐sites in perovskites. [ABSTRACT FROM AUTHOR]

Fast and high‐linearity detection of fast neutron is vital for special nuclear material seeking, nuclear accident emergency response, nondestructive neutron imaging, and neutron cancer therapy. Neutron scintillators with fast time resolution and linear energy response are indispensable for precisely acquiring the energy and temporal evolution of fast neutron, but none of the conventional neutron scintillators, whether organic, two‐component or inorganic, have performed well in this regard. To address these challenges, it is urgent to develop novel neutron scintillators. Here, 2D hybrid perovskite single crystals (C4H12N)2PbBr4 (BA2PbBr4) successfully combined with fast response time of 2.66 ns and linear energy response to fast neutrons, γ ray, and α particle, is reported. The rapid response time and linear energy response of 2D hybrid perovskite scintillator originate from intensive states density of lead halide frameworks, which are the key fluorescence emitters under neutron irradiation. This effectively suppresses the ionization quenching effect during the fluorescence process. This work represents a milestone in fast neutron detection, demonstrating a new type of neutron scintillator based on 2D hybrid perovskite single crystals with fast and high‐linearity detection characteristics, having great potential in high precision neutron spectrum measurement and nuclear reaction kinetics monitoring. [ABSTRACT FROM AUTHOR]

The search for efficient, re-absorption-free scintillators has recently focused the attention on antimony-based halides, which exhibit largely Stokes shifted luminescence due to radiative recombination of excitons self-trapped (STE) in strongly Jahn-Teller distorted Sb3+ color centers. Here, the synthesis of a hybrid structure is reported with chemical formula (C13H14N3)3SbCl6 consisting of spatially isolated [SbCl6]3- octahedra separated by organic N, N'-diphenylguanidinium (Gua) molecules. The optical properties of this material are mainly determined by the inorganic component and are characterized by a pronounced Stokes shift of "1.3 eV and a room-temperature photoluminescence (PL) efficiency of up to 85%. Remarkably, highly efficient radioluminescence (RL) is observed with scintillation light yields of "2000 ph MeV-1 using both soft X-rays and a 124 keV gamma source. Temperature-dependent PL and RL measurements confirm the minor role of non-radiative channels, which are completely suppressed below 100 K. Thermally stimulated luminescence measurements suggest that the traps in Gua3SbCl6 crystals have a significantly large energy depth distribution below the absorbing state. [ABSTRACT FROM AUTHOR]

Lead‐free metal halides have recently received sustained attention because of their nontoxicity, low‐cost, as well as excellent stability and optoelectronic properties. However, most of the reported lead‐free metal halides are synthesized via slow solution‐processing at high temperature in toxic solvents, which may impede their commercial applications. Here, a solvent‐free strategy is proposed to synthesize inorganic rubidium copper halides (Rb2CuX3, X = Cl, Br) at room temperature, which exhibit efficient violet emission dominated by a self‐trapped excitons (STEs) mechanism and attractive stabilities against ultraviolet illumination and heating. Thus, Rb2CuX3 powders are employed as emitters and scintillators applied in wireless light communication and X‐ray imaging technologies. Under orthogonal frequency division multiplexing modulation, emitters demonstrate a broad −3 dB bandwidth of 26.3 MHz and a high received data rate of 205.1 Mbps. Additionally, flexible scintillation films based on as‐prepared powders are fabricated and show outstanding X‐ray scintillation properties, including a high spatial resolution of 18.1 lp mm−1 and a low detection limit of 104 nGyair s−1, as well as promising imaging performance for irregular objects. These results suggest large‐scale production of nontoxic Rb2CuX3 and their potential commercialization in fields of high‐speed light communication and X‐ray radiography. [ABSTRACT FROM AUTHOR]

Ferroptosis therapy induced by iron‐catalyzed Fenton reaction has offered enormous opportunities for tumor therapy. Unfortunately, high catalytic activity ferrous (Fe2+)‐based therapeutic agent has remained challenging due to the instability of Fe2+. Herein, an X‐ray‐activated Fe2+ supply platform, termed "PFCN", containing the core of CaWO4 nanoscintillator to emit ultraviolet (UV) light and Fe3O4 decorated on the surface to deliver excessive Fe2+ is proposed. Under X‐ray excitation, the UV light emitted by CaWO4 can catalyze ferric (Fe3+) to generate Fe2+, which further cascades the Fenton reaction to induce highly toxic hydroxyl radicals generation. More importantly, immunogenic cell death‐associated immunotherapy is simultaneously triggered during this process. Experiments conducted in vitro and in vivo revealed that X‐ray‐triggered PFCN shows superior tumor therapeutic efficacy, contributing i) enhanced radiotherapy; ii) X‐ray‐activated ferroptosis therapy; and iii) ferroptosis/radiotherapy‐induced immunotherapy. Besides, PFCN can be utilized as an MR/CT dual‐mode imaging contrast agent for tumor diagnosis and treatment monitoring. The study provides a novel example of an X‐ray‐activated ferrous‐regeneration platform for imaging‐guided augmenting tumor ferroptosis/immunotherapy [ABSTRACT FROM AUTHOR]

Fast neutron and X‐ray imaging are considered complementary nondestructive detection technologies. However, due to their opposite cross‐sections, development of a scintillator that is sensitive to both fast neutrons and X‐rays within a single‐material framework remains challenging. Herein, an organic–inorganic hybrid perovskite (C4H9NH3)2PbBr4 (BPB) is demonstrated as a scintillator that fully meets the requirements for both fast neutron and X‐ray detection. The hydrogen‐rich organic component acts as a fast neutron converter and produces detectable recoil protons. The heavy atom‐rich inorganic fraction efficiently deposits the energy of charged recoil protons and directly provides a large X‐ray cross‐section. Due to the synergy of these organic and inorganic components, the BPB scintillator exhibits high light yields (86% of the brightness of a commercial ZnS (Ag)/6LiF scintillator for fast neutrons; 22 000 photons per MeV for X‐rays) and fast response times (τdecay = 10.3 ns). More importantly, energy‐selective fast neutron and X‐ray imaging are also demonstrated, with high resolutions of ≈1 lp mm−1 for fast neutrons and 17.3 lp mm−1 for X‐rays; these are among the highest resolution levels for 2D perovskite scintillators. This study highlights the potential of 2D perovskite materials for use in combined fast neutron and X‐ray imaging applications. [ABSTRACT FROM AUTHOR]

Copper metal halides have emerged as a strong contender in the scintillator field due to the self‐trapped excitons (STEs) mechanism. However, their development has been hindered by the preparation process. Single crystals have long growth cycles and cannot achieve large areas and flexibility. Quantum dots have a low yield and can easily cause chemical pollution, and the thickness of films prepared by the spin coating cannot be controlled. To address these challenges, a new method for preparing Cs3Cu2Cl5 using sequential vacuum evaporation is developed. This allows successful preparation of large‐area (≈100 cm2) and flexible films. The STEs mechanism of Cs3Cu2Cl5 gives it unique properties such as a large Stokes shift that reduces self‐absorption effects, and a wide full width at half‐maximum that improves coupling with photodiodes. Therefore, Cs3Cu2Cl5 is applied to X‐ray imaging with a light yield of ≈30 000 photons MeV−1, a spatial resolution of over 10 lp mm−1, and a low detection limit below 0.8 µGyair s−1. In addition, the flexible Cs3Cu2Cl5 film enables effective dynamic imaging and clear imaging on non‐planar objects. It also exhibits good resistance to harsh environments, maintaining good imaging performance after 150 days. It is believed that sequential vacuum evaporation provides an important idea for preparing scintillators. [ABSTRACT FROM AUTHOR]

Substitutional lanthanide doping of 2D transition metal dichalcogenides (TMDs) is expected to be a promising strategy to engineer optical, electronic, and optoelectronic properties of TMDs. Understanding the interactions between lanthanide dopants and 2D TMDs host is one of the key problems to be resolved for their profound research studies. Herein, the interactions between Ce dopants and monolayer WS2 in a physical vapor deposition grown Ce‐doped WS2 monolayer are studied by combining scanning tunneling microscopy with optical characterizations with high spatial and temporal resolution. It is found that the highly anisotropic crystal field can effectively split the energy levels of the Ce dopants' f orbital. The electrons in the split energy levels can bind the holes in the valence band maximum of the Ce‐doped WS2, forming optical bright excitons. These excitons collide with the free A excitons when increasing the pump fluences, reducing the A exciton's lifetime. This study may be beneficial for the design and fabrication of optical, electronic, and optoelectronic devices based on lanthanide‐doped TMDs. [ABSTRACT FROM AUTHOR]

Scintillators with high light yield, low detection limit, large X‐ray attenuation efficiency as well as stable and nontoxic compositions are of great importance for radiation detection applications. Here, 0D (C8H20N)2Cu2Br4 single crystals are obtained and show blue emission peaking at 468 nm with a near‐unity photoluminescence quantum yield of 99.7%, a large Stokes shift of 148 nm (i.e., negligible self‐absorption), and a good environmental stability along with strong X‐ray absorption capability. Moreover, a high light yield of up to ≈ 91 300 photons/MeV and a low detection limit of 52.1 nGyair s−1 are realized, which is more than one hundred times lower than the dose rate of 5.5 µGyair s−1 required for X‐ray medical diagnostics. (C8H20N)2Cu2Br4 ceramic wafer scintillation screen is fabricated by a cold pressing sintering process, and the clear contrast images of opaque metal box and electronic component with a spatial resolution of 9.54 lp mm−1 are realized. This study not only designs a new lead‐free metal halide scintillator, but also develops a universal strategy for the preparation of large‐sized scintillator screen in nondestructive X‐ray imaging. [ABSTRACT FROM AUTHOR]

The development of metal‐halide perovskite nanocrystals (NCs) that yield bright and stable emission is of great importance. Previous reported perovskite NCs are mostly based on APbX3‐type family fabricated via ligand‐ or surfactant‐assisted chemical approaches. However, realizing bright and stable emission remains a challenge because of desorption of ligands/surfactants during long‐term operation. Herein, Ruddlesden–Popper (RP)‐type (A)2(MA)n‐1PbnBr3n+1 NCs with size less than Bohr radius stabilized in mesoporous silica scaffold, which are prepared in situ via physical approach at low temperature are introduced. The RP NCs in mesoporous silica exhibit the formation of spatially and electronically separated quantum wells, efficient energy funneling between different n phases for bright emission (photoluminescence quantum yields of ≈99%), high irradiation stability (T70 = 110 days), and long‐term stability (T90 = 110 days). These RP NCs have broad potential for bright light‐emitting diodes, high‐resolution PL imaging, and waterproof inks. Importantly, for the first time, stretchable perovskite X‐ray scintillator is demonstrated with excellent X‐ray imaging with resolution greater than 14 line pairs mm−1. These findings offer a paradigm to motivate future research toward stable and efficient perovskite optoelectronics. [ABSTRACT FROM AUTHOR]

The development of metal‐halide perovskite nanocrystals (NCs) that yield bright and stable emission is of great importance. Previous reported perovskite NCs are mostly based on APbX3‐type family fabricated via ligand‐ or surfactant‐assisted chemical approaches. However, realizing bright and stable emission remains a challenge because of desorption of ligands/surfactants during long‐term operation. Herein, Ruddlesden–Popper (RP)‐type (A)2(MA)n‐1PbnBr3n+1 NCs with size less than Bohr radius stabilized in mesoporous silica scaffold, which are prepared in situ via physical approach at low temperature are introduced. The RP NCs in mesoporous silica exhibit the formation of spatially and electronically separated quantum wells, efficient energy funneling between different n phases for bright emission (photoluminescence quantum yields of ≈99%), high irradiation stability (T70 = 110 days), and long‐term stability (T90 = 110 days). These RP NCs have broad potential for bright light‐emitting diodes, high‐resolution PL imaging, and waterproof inks. Importantly, for the first time, stretchable perovskite X‐ray scintillator is demonstrated with excellent X‐ray imaging with resolution greater than 14 line pairs mm−1. These findings offer a paradigm to motivate future research toward stable and efficient perovskite optoelectronics. [ABSTRACT FROM AUTHOR]

Herein, the first study on the scintillation properties of CsCu2X3 and Cs3Cu2X5 (where X: Cl−, Br−, I−) is presented, describing their charged particle‐induced luminescence involving electrons, protons, α‐particles, and heavy ions, as well as revealing their capabilities on the timing and spectroscopic evaluation of single‐particle events. The thin layers are prepared with a simple and cost‐effective deposition procedure, without the incorporation of external dopants, exploiting the intrinsic radiative recombination observed in low‐dimensional perovskites. The combined effect of the high binding energy and localized stability of self‐trapped excitons, large Stokes shift, defect tolerance, and the high excitation density along the particle track leads to the emergence of boosted scintillation pulses. The observations demonstrate the first use of inorganic thin‐film scintillators with optical pulse characteristics and light yield competitive with doped single crystal scintillators, while also providing improved structural and functional stability under extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Halide perovskites are an emerging scintillator material for X‐ray imaging. High‐quality X‐ray imaging generally requires high spatial resolution and long operation lifetime, especially for targeted objects with irregular shapes. Herein, a perovskite "polymer–ceramics" scintillator, in which the halide perovskite nanocrystals are grown inside a pre‐solidified polymer structure with high viscosity (6 × 1012 cP), is designed to construct flexible and refreshable X‐ray imaging. A nucleation inhibition strategy is proposed to prevent the agglomeration and Ostwald ripening of perovskite crystals during the subsequent precipitation process, enabling a high‐quality polymer–ceramics scintillator with high transparency. This scintillator‐based detector achieves a detection limit of 120 nGy s–1 and a spatial resolution of 12.5 lp mm–1. Interestingly, due to the anchoring effect of the exfoliated atoms provided by the polymer matrix, the scintillator film can be refreshed after a long duration (≥3 h) and high dose (8 mGy s–1) irradiation. More importantly, this inherent characteristic overcomes the long operation lifetime issue of perovskites‐based scintillators. Hence, the authors' exploration of the polymer–ceramics scintillator paves the way for the development of flexible and durable perovskite scintillators that can be produced at a low operation cost. [ABSTRACT FROM AUTHOR]

Both semiconductors and scintillators have their own advantages in direct and indirect X‐ray detection, respectively. However, they are also limited by their intrinsic properties and detection mechanisms. Here, a low‐cost and large‐area flat X‐ray detector is reported by combining a cesium silver bismuth bromide (Cs2AgBiBr6) perovskite semiconductor with a ethylenebis‐triphenylphosphonium manganese (II) bromide ((C38H34P2)MnBr4) scintillator through fast tableting processes. Cs2AgBiBr6 and (C38H34P2)MnBr4 can attenuate the X‐ray photons to induce charge carriers that are collected through the continuous Cs2AgBiBr6 grains. (C38H34P2)MnBr4 blocks the Cs2AgBiBr6 ions migration paths at the grain boundaries to reduce the device dark current/noise and improves the working stability. Most charges generated by (C38H34P2)MnBr4 are transferred to the adjacent Cs2AgBiBr6, and recombined charges radiate light through scintillation, which will be further absorbed by the surrounding Cs2AgBiBr6 perovskite, and further induce collectable charges for indirect X‐ray detection, avoiding the unwanted light scattering, self‐absorption, or afterglow effects of scintillators. The hybrid X‐ray detector displays a high sensitivity of 114 µC Gyair−1 cm−2 to 120 keVp hard X‐rays with a lowest detectable dose rate of 0.2 μGyair s−1, showing 75 times lower detection limit compared to (C38H34P2)MnBr4 scintillator, which provides a new path for X‐ray flat‐panel design. [ABSTRACT FROM AUTHOR]

Lead halide perovskites (LHP) are rapidly emerging as efficient, low‐cost, solution‐processable scintillators for radiation detection. Carrier trapping is arguably the most critical limitation to the scintillation performance. Nonetheless, no clear picture of the trapping and detrapping mechanisms to/from shallow and deep trap states involved in the scintillation process has been reported to date, as well as on the role of the material dimensionality. Here, this issue is addressed by performing, for the first time, a comprehensive study using radioluminescence and photoluminescence measurements side‐by‐side to thermally‐stimulated luminescence (TSL) and afterglow experiments on CsPbBr3 with increasing dimensionality, namely nanocubes, nanowires, nanosheets, and bulk crystals. All systems are found to be affected by shallow defects resulting in delayed intragap emission following detrapping via a‐thermal tunneling. TSL further reveals the existence of additional temperature‐activated detrapping pathways from deeper trap states, whose effect grows with the material dimensionality, becoming the dominant process in bulk crystals. These results highlight that, compared to massive solids where the suppression of both deep and shallow defects is critical, low dimensional nanostructures are more promising active materials for LHP scintillators, provided that their integration in functional devices meets efficient surface engineering. [ABSTRACT FROM AUTHOR]

This study shows the first use of inorganic thin-film scintillators with optical pulse characteristics and light yield competitive with doped single crystal scintillators, while also providing improved structural and functional stability under extreme environmental conditions. Alpha-particle detections, cesium-copper-halides, detectors, ionizing radiations, perovskites, polycrystalline, scintillators Keywords: alpha-particle detections; cesium-copper-halides; detectors; ionizing radiations; perovskites; polycrystalline; scintillators EN alpha-particle detections cesium-copper-halides detectors ionizing radiations perovskites polycrystalline scintillators 1 1 1 11/29/22 20221124 NES 221124 B Alpha-Particle Detections b In article number 2206645, Csaba Janáky, Mátyás Hunyadi, and coworkers demonstrate the spectroscopic detection of charged particles with cesium copper halide thin films. [Extracted from the article]