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Scintillators with high spatial‐resolution and high‐stability are highly desirable for X‐ray imaging applications at unpredictable environments. To challenge state‐of‐the‐art technology, it is necessary to design high thermal stable scintillators with high‐resolution and high light yield. In this work, the zero‐thermal‐quenching Lu3Al5O12:Ce3+ (LuAG: Ce3+) transparent ceramics (TCs) is synthesized with high optical transparency. The thermoluminescence (TL) curves of the as‐obtained TCs demonstrate that the formation of the oxygen vacancies, acting as the trapping centers, can capture the carriers and then contribute to the enhancement of its thermals stability via the thermal compensation effect. The exceptional thermal‐stability of the TCs scintillator endows the monitoring of the dynamic changes of the internal structure of the objective samples without any ghosting effects during heating. In addition, given the ultra‐high uniform, transparency, and fast light decay of the TCs scintillator, the excellent spatial resolution (≈112 lp mm−1) of the X‐ray microscopic imaging is realized. These results undeniably demonstrate that the as‐obtained LuAG: Ce3+ TCs have great prospects for advancement in X‐ray detectors. [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]

Optical materials have attracted much attention in anti‐counterfeiting applications due to their visualization and multi‐emission modes. However, the unit occupancy predestines the material to only monochromatic emission, inhibiting the application of optical materials in advanced information encryption. Here, a green to yellow to deep‐red phosphor is reported in a Mn2+‐activated garnet compound Ca2YMgScSi3O12: Mn2+ (CYMSS: Mn2+), originating from the abundant lattice sites occupying within the crystal structure by Mn2+ ions. Three different photoluminescence (PL) emission bands peaked at 517, 576, and 720 nm from 4T1 (G) → 6A1 (S) are observed, which are attributed to the substitution of [Sc/MgO6] octahedron and [Ca/YO8] dodecahedron sites by Mn2+ ions, respectively. Hence, tunable emissions from green to deep‐red are realized in single Mn2+ doping by switching the excitation source of ultraviolet (UV)/blue and X‐ray, which can be further regulated by varying the Mn2+ concentration. Multi‐position occupying, color‐tunable light‐emitting materials offer the possibility of more advanced optical information encryption. [ABSTRACT FROM AUTHOR]

Ultrahigh‐resolution X‐ray detection has always been a goal pursued in industrial inspection and medical diagnosis. However, the resolution of the corresponding image generally suffers from serious light scattering and crosstalk. Here, a low‐temperature thermoplastic scintillator ink of [Bmmim]2MnCl4 (Bmmim = 1‐butyl‐2,3‐dimethylimidazolium) is designed, achieving an astonishing spatial resolution of over 22 lp mm−1 (≥22.5 µm). A customized X‐ray imaging can be realized with the as‐explored [Bmmim]2MnCl4 scintillator to the targets through brushing feasibly exhibiting a high adhesion and processability thanks to the superior rheological properties. It is demonstrated that the coordination number determines the melting point of the corresponding scintillator, and an appropriate melting point (323 K) endows a superior viscosity of the sample as print ink. Accordingly, the as‐explored scintillator not only exhibits a high light output with 3.63 times of the commercial Bi4Ge3O12 (10 000 photons MeV−1) under steady‐state X‐ray illumination but also performs excellent recyclability even after 100 re‐uses. This work brings a new perspective for solving the problems of light scattering and light crosstalk for X‐ray imaging, as well as promoting the development of scintillator ink for recycling utilization. [ABSTRACT FROM AUTHOR]

As a new green energy‐harvesting technology, the electrification mechanism and output performance of triboelectric nanogenerators (TENGs) have become the research focuses and difficulties. Based on the basic principles of contact and damage mechanics, a five‐stage micro‐contact model is proposed on the interface of sliding TENGs friction subsurface. Experimental bench is built to complete the experimental validation and factors affecting the output performance of TENGs are experimentally investigated. In the results, it is shown that the contact form of the asperities on the surface of the friction subsurface determines the real contact area and the form of energy conversion, and the dynamical processes between the asperities are influenced by the velocity, load, and material, which further affect the elastic/plastic change of the friction surface and the directional transfer of contact electrons. Normal loading promotes the density and efficiency of electron transfer between the interfaces of the friction sub‐interfaces, but the electrical output performance of the system is no longer enhanced when the load is too high (≥10 N). The faster sliding speed is conducive to improving the output performance of the horizontal sliding TENG in a certain range (0.005–0.100 m s−1). [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML) materials are widely used in information storage, stress sensing, and structural health monitoring due to their simplicity, nondestructiveness, and real‐time sensing characteristics. However, the currently reported ML films suffer from high‐temperature decomposition, opacity, and unstable ML properties, which seriously limits their applications. Herein, a transparent TbBO3 glass‐ceramic (GCs) with significant ML performance is explored. A large number of Si‐O and B‐O tetrahedra in the glass matrix greatly improves the structural stability. Meanwhile, the disordered atomic arrangement reduces the obstacles in the light propagation process, making it highly transparent. Furthermore, femtosecond laser irradiation produces an ultra‐deep trap of 517 K, which makes its ML performance highly stable. Based on this material, an aircraft stress safety monitoring system that can accurately pinpoint where the aircraft window is hit is designed. Therefore, this work provides a new strategy for the design of highly stable and transparent ML materials. [ABSTRACT FROM AUTHOR]

The development of highly stable and ultra‐long organic room temperature phosphorescence (RTP) materials holds great promise for applications in anti‐counterfeiting and information protection. To improve the encryption level, the exploration of organic materials with tunable phosphorescence and afterglow features is in urgent need. Hereby, a series of long‐lived organic systems with RTP is developed by incorporating benzocarbazole derivatives into a polyvinyl alcohol (PVA) matrix (BCz@PVA). Notably, the BCz@PVA film exhibits outstanding RTP behavior with an ultralong phosphorescence lifetime (τp) of 2.09 s, high phosphorescence quantum yield (Φp) of 46.335%, and an ultra‐long afterglow duration of 15 s. Moreover, the BCz@PVA film maintains excellent RTP performance even after being placed in ambient conditions for 60 days. Theoretical calculations reveal that the excellent RTP performance of BCz@PVA film is attributed to the stronger intermolecular interactions, the smaller energy gap (ΔEst) between the singlet and triplet states, and stable molecular stacking mode. Furthermore, color‐tunable photoluminescence (PL), distinct τp, and afterglow duration are successfully achieved by adjusting the position of the Br substituent on the benzene ring. Based on their diverse RTP performances and excellent stability, the corresponding BCz@PVA film provides successful application for multi‐level high‐security anti‐counterfeiting and information protection. [ABSTRACT FROM AUTHOR]

Monitoring the real‐time quality and validity of thermo‐sensitive foods during storage and transportation can be achieved with time‐temperature indicators (TTIs). However, the available TTIs still need to be improved in terms of accuracy, recoverability, environmental tolerance, and quantitative monitoring. Here, a novel TTI based on the optical signals originating from the as‐explored Sr3Y2Ge3O12: Mn2+, Er3+ (SYGO: Mn2+, Er3+) phosphor is developed. Thanks to the fact that the release of the captured carriers is tightly related to the storage time and ambient temperature, distinct optical signals of the as‐obtained TTI under multi‐stimulus (980 nm laser irradiation, thermal stimulation, and mechanical force) can be distinguished to judge the validity of temperature‐sensitive products. This work reveals the promising potential of SYGO: Mn2+, Er3+ phosphors with cryogenic optical storage properties as advanced TTIs, especially for packaged products in cold chain logistics. [ABSTRACT FROM AUTHOR]

Metal‐halide perovskites have emerged as one of the most promising contenders for the next‐generation X‐ray scintillators on account of their large absorption coefficients, high light yields, and low‐cost fabrication. However, the existing X‐ray scintillators are plagued either by poor stability or high toxicity. Here, highly stable and flexible CsCu2I3@polymethyl methacrylate (PMMA) composite films are fabricated simply by a facile one‐step drop‐coating technique. Benefiting from the reasonable light yields (24 100 photons MeV−1), short photoluminescence decay time (207 ns), and flat surface, a low detection limit of 39 nGyair s−1 and a record‐high resolution of up to 25 lp mm−1 are demonstrated in these CsCu2I3@PMMA composite films. The X‐ray imaging tests show that the CsCu2I3@PMMA composite films display excellent properties in the dynamic and irregular objects imaging. In addition, the CsCu2I3@PMMA composite films exhibit a desirable endurance to the high‐energy X‐ray's irradiation and the water erosion (photoluminescence quantum yield remains up of 90% of its initial value even after submersion in water for 300 h). This work provides a potential to develop eco‐friendly and highly stable halide perovskite materials for high‐resolution X‐ray imaging. [ABSTRACT FROM AUTHOR]

High‐resolution X‐ray imaging is increasingly required for medical diagnosis and large‐area detection. However, the issues of scattering and optical crosstalk are limiting the spatial resolution of the indirect X‐ray imaging. In this study, a feasible and efficient strategy is proposed to in situ synthesize flexible Cs3Cu2I5:2%In+@paper as a superior scintillator film, which can be scaled up to an ultra‐large area of 4800 cm2. The as‐obtained Cs3Cu2I5:2%In+@paper performs a fascinating photoluminescence quantum efficiency up to 88.14%, a steady state light yield of 70169 photons/MeV, and spatial resolution of 15 lp mm−1. Moreover, the suppressed physical scattering and optical crosstalk of the corresponding film are demonstrated. Accordingly, this work explores a feasible fabrication of customizable scintillation films with large area for high‐resolution X‐ray detection. [ABSTRACT FROM AUTHOR]

Thermal disturbance deteriorates the radiative transitions of up‐conversion phosphor, leading to decreased emission intensity at high operation temperatures. In this work, a thermal‐favored Yb3+/Nd3+ co‐doped KGaGeO4 up‐conversion phosphor with a negative thermal quenching behavior is explored. The as‐developed phosphor performs a one‐photon anti‐Stokes emission and exhibits a remarkable enhancement for the rise of ambient temperature reaching 653 K. It is demonstrated that the fascinating thermal behavior of the up‐conversion procedure is attributed to the enhanced energy transfer from the corresponding sensitizers to the activators by phonon assistance. Moreover, the microscopic dynamical process of phonon assistance and annihilation is revealed by introducing Er3+ ions as a probe. These results not only shed light on the phonon‐assisted strategy to build a highly efficient anti‐Stokes emission system but also open prospects for constructing phonon‐favored transitions with nonthermally coupled emissions to realize luminescence thermometry for their distinct thermal responsivity. [ABSTRACT FROM AUTHOR]

X‐ray time‐lapse imaging allows for precise radiographic imaging of the item after X‐ray has been terminated, which is important for simplifying legacy X‐ray detectors and avoiding health hazards caused by ionizing radiation during the imaging process. However, the premature discharge of carriers from shallow traps at room temperature over time leads to the loss of imaging information, making an accurate representation of the recorded information to achieve accurate time‐lapse imaging still a challenge. Here, it is demonstrated that monodispersed NaLuF4: Tb3+ nanocrystals with the replacement of Na+ by Cs+ ions in the lattice matrix realize a superior X‐ray time‐lapse imaging. It is found that the incorporation of Cs+ ions amplifies the deep trap storage capacity, which ensures the stable presence of carriers under thermal perturbation at room temperature. Imaging information with a spatial resolution of 12.0 lp mm−1 can be accurately represented even after the irradiation of the X‐ray has been terminated for 192 h. X‐ray time‐lapse imaging not only allows accurate reading of long‐term stored imaging information but also endows the visualization of X‐ray imaging independent of the dangerous radiation, which will offer great opportunities for X‐ray inspection on a larger scale. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D)‐halide perovskites have been enriched over recent years to offer remarkable features from diverse chemical structures and environmental stability endowed with exciting functionalities in photoelectric detectors and phosphorescence systems. However, the low conversion efficiency of singlet to triplet in 2D hybrid halide perovskites reduces phosphorescence lifetimes. In this study, the long persistent luminescence of 2D all‐inorganic perovskites with a self‐assembled 2D interlayer galleries structure is investigated. The results show that the decay time of the long persistent luminescence increases from 450 s to 600 s, and the luminescence color changes from cyan to orange, and the thermal stability of photoluminescence enhances dramatically after replacing Cd2+ by appropriate Mn2+ ions in 2D Cs2CdCl4 Ruddlesden‐Popper phase perovskites. Furthermore, diversified anti‐counterfeiting modes are fabricated to highlight the promising applications of Cs2CdCl4 perovskite systems with tunable persistent luminescence in advanced anti‐counterfeiting. Therefore, our studies provide a novel model for realizing tunable long persistent luminescence of perovskite with 2D self‐assembled layered structure for advanced anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Lithium metal has been considered one of the most promising anodes for next‐generation rechargeable batteries, but its practical application is largely hindered by the uncontrollable dendrite growth and infinite volume change. Here, inspired by superior catalytic effects of single‐atom catalysts, carbon‐supported single atomic Co with asymmetric N, O‐coordination (Co‐N/O) is developed for Li metal battery. Experimental results and theoretical calculations indicate that single atomic Co atoms with asymmetric N, O‐coordination present enhanced binding ability toward Li in comparison with N‐coordinated atomic Co site and isolated O site, enabling uniform Li plating/stripping. Moreover, the asymmetric N, O‐coordination around Co atoms induces co‐activation effects, lowering the energy barriers toward Li+ to Li0 conversion and largely promoting the deposition kinetics. When used as a Li deposition host, the Co‐N/O achieves a high average coulombic efficiency of 98.6% at a current density of 1 mA cm−2 and a capacity of 2 mAh cm−2, long cycling life of 2000 h in symmetrical cells, and excellent rate performance (voltage hysteresis of 23 mV at 8 mA cm−2). This work provides a comprehensive understanding of single atomic metals with asymmetric heteroatom coordination in the design of Li metal anode. [ABSTRACT FROM AUTHOR]

With the fast‐growing amount of data, the state‐of‐the‐art optical data storage has become a front‐runner in the competing data storage technologies. However, two‐dimensional (2D) spatial resolution in the conventional optical data storage media has almost reached the limit. Herein, LiGa5O8:Cr3+ nanoparticles (NCs) precipitated in situ from a transparent medium are prepared. The transparent LiGa5O8:Cr3+ glass ceramics show excellent deep‐trap carriers storage ability under blue light irradiation and can realize the bit‐by‐bit optical data in 3D space for write‐in and read‐out in a photon trapping/detrapping mode. Moreover, this optical storage mechanism is also extended to 4D by realizing temperature optical encryption. Notably, the written information can still be clearly displayed even after being recorded for 200 days. This work enables 4D high‐precision storage of information and provides new insights into the design and fabrication of next‐generation storage materials. [ABSTRACT FROM AUTHOR]

Mechanical sensors execute multi‐mode response to external force, which are cornerstones for applications in human–machine interactions and smart wearable equipments. Nevertheless, an integrated sensor responding to mechanical stimulation variables and providing the information of the corresponding signals, as velocity, direction, and stress distribution, remains a challenge. Herein, a Nafion@Ag@ZnS/polydimethylsiloxanes (PDMS) composite sensor is explored, which realizes the description of mechanical action via optics and electronics signals simultaneously. Combined with the mechano‐luminescence (ML) originated from ZnS/PDMS and the flexoelectric‐like effect of Nafion@Ag, the corresponding explored sensor achieves the detection of magnitude, direction, velocity, mode of mechanical stimulation, and the visualization of the stress distribution. Moreover, the outstanding cyclic stability, linearity response character, and rapid response time are demonstrated. Accordingly, the intelligent recognition and manipulation of a target are realized, which indicate a smarter human–machine interface sensing applied for wearable devices and mechanical arms can be expected. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML) materials with long‐wavelength emission bands are essential for future in vivo bioimaging, non‐destructive testing of solids, etc. The lack of a defined mechanism, however, prevents the application of near infrared ML materials above 650 nm in several new fields. Here, the addition of Ga3+ ions to Y3Al5O12: Cr3+ manipulates matrix microstructure evolution, boosting near‐infrared (NIR) zero‐phonon line (ZPL) stress optical output of the Cr3+ ion at 688 nm. The key factor changing the crystal field intensity Dq/B due to the addition of Ga3+ ions is what causes the luminescence amplification of ZPL. The ML fabricated by composite polydimethylsiloxane and Y3Al4GaO12: Cr3+ (YAGG: Cr3+) may penetrate chicken feet epidermal tissue and 4 mm pork tissue thanks to the strong NIR ZPL emission of YAGG: Cr3+ phosphor. This discovery of enhancing near‐infrared ZPL intensity by solid solution provides us with a new technique for optimizing NIR ML materials, as well as a new prospect for NIR ML materials in biological applications. [ABSTRACT FROM AUTHOR]

Glass scintillators have several benefits compared to the currently used single or polycrystalline scintillators, including non‐hygroscopicity, mechanical ruggedness, ease of producing customizable shapes, and low‐cost synthesis. The combination of the inert glass matrix and the embedded highly scintillating center render them significant materials for medical imaging and therapy, non‐destructive probing, nuclear monitoring, and high‐energy physics. Recently, great progress has been made in exploring new kinds of glass scintillator materials, improving imaging resolution for radiation detection, and developing an enormous range of commercial products. However, the majority of efforts have been devoted to the variation of materials, while rationally designing this new family of scintillators toward expected properties and applications is still lacking. In this review, the focus is specifically on advances in glass scintillators, including the scintillation fundamentals, material designing rule, and current application status, as well as future challenges and future directions. [ABSTRACT FROM AUTHOR]

A reasonable width of the coal pillar is very important to the surrounding rock control of the gob‐side roadway. An unreasonable width of the coal pillar will make the roadway to be located within the range of strong mining influence, leading to severe deformation of the roadway. Severe subsidence at the coal pillar side of the roof and serious coal pillar deformation are problems caused by strong dynamic pressure due to mining in the gob‐side coal roadway. This paper studies the surrounding rock instability mechanism and rational coal pillar width of the gob‐side coal roadway under the influence of intense dynamic pressure. The results show that: (1) Under the condition of large mining height, the roadway overburden is a hinged structure, and an unreasonable coal pillar width makes the gob‐side coal roadway to be located below the main roof fracture line. The rotary movement of the key block of the main roof is the main reason for the roadway deformation. (2) According to the evolution law of stress field, displacement field and plastic zone of surrounding rock of roadway under different coal pillar widths during roadway driving and mining were studied, and it is concluded that a 6‐m‐width coal pillar is the most reasonable. (3) Based on the stress distribution and plasticizing range of surrounding rock in a narrow pillar roadway, the combined support scheme of "anchor cable + grouting + single prop" is proposed and applied to engineering practice. The practice results show that the roadway deformation is well controlled, and the safe mining of the working face is realized. [ABSTRACT FROM AUTHOR]

Herein, the grown‐into‐glass (GIG) CsPbBr3:Ln3+ (Ln = La, Lu) nanocrystals (NCs) are designed and fabricated using an in situ nanocrystallization method. It is shown that a substitution of Pb2+ sites with Ln3+ ions leads to a blueshift of emission position induced by an increase of the bandgap of CsPbBr3. Additionally, the GIG‐samples are found to feature excellent photoluminescent (PL) properties after being immersed respectively in water for 300 days at room temperature, boiling water for 12 h, and corrosive environments for 24 h, as well as recoverable PL intensity either after several cycles of heat‐cooling experiments or after being continuously exposed to a 405 nm laser irradiation. Besides, a spontaneous enhancement of 20‐25% of emission intensity during the 1‐2.5 hours' stage of a 405 nm laser irradiation, attributed to the radiative recombination of charge carriers that can be de‐trapped from trapping levels upon the laser light irradiation and that then spontaneously reinforces the emission intensity, is observed in the GIG‐CsPbBr3:Ln3+ NCs. Finally, a white light‐emitting prototype, with a CIE chromaticity coordinate at (0.4110, 0.3706), a color rendering index of 89 and a correlated color temperature of 3363 K is realized by combining the GIG‐CsPbBr3 NCs, YAG:Ce and CaWO4:Eu phosphors. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbBr3 perovskite nanocrystals (NCs) have stimulated the enthusiasm of the research on light emitting diodes (LEDs), laser, X‐ray detection, and information encryption, thanks to their excellent optical performance. Exploiting CsPbBr3 NCs with fascinating long persistent luminescence (LPL) is significantly important for expanding their potential applications. In this work, the room temperature LPL is successfully achieved in CsPbBr3 glass‐ceramics (GCs) through the optical write with a femtosecond (fs) laser. The carriers captured by the generated trapping centers for the crack of non‐bridged oxygen bonds in the glassy matrix are released by the thermal disturbance of room temperature. Moreover, the LPL performance is modulated flexibly for doping with La3+, Dy3+, Nd3+, and Lu3+ ions in the CsPbBr3 GCs, endowing the successful construction of a time‐resolved anti‐counterfeiting mode. Furthermore, the high stability and high color purity (97.04%) of the as‐obtained CsPbBr3 GCs are demonstrated. The results open a window for fs laser induced perovskite with myriad applications in optical storage devices. [ABSTRACT FROM AUTHOR]

The piggyback thrust wedge is a common structural style in thrust belts, which controls the lateral arrangement of hydrocarbon distribution. This study conducted physical simulation experiments of structural deformation and hydrocarbon accumulation by using the piggyback thrust wedge as the geological model. According to the experimental results, hydrocarbon accumulation patterns were obtained by investigating the evolutionary history of the fault‐sealing performance while inverting the coupling relationship between the fault evolution and hydrocarbon accumulation. The structural deformation experiment showed that the evolution of the fault displacement and dip angle was characterized by gradual and staged progress. The kaolin smear continuity deteriorated with fault evolution. The soybean oil accumulation experiment demonstrated that the fault‐sealing performance in the rear of the thrust wedge was inferior to that in the front. Hydrocarbon migration was mostly lateral in the front of the thrust wedge and mainly vertical in the rear. Quantitative analysis showed that the fault‐sealing performance had three closed, partially closed, and open stages, which gradually deteriorated with the structural evolution. Three hydrocarbon accumulation patterns were identified in the piggyback thrust wedge: synchronized, adjustment, and non‐adjustment patterns. The evolution of the structural deformation and faults‐sealing performance resulted in spatio‐temporal differences in hydrocarbon accumulation in the thrust belts of central‐western China. The front of the thrust wedge had a higher exploration potential than the rear. [ABSTRACT FROM AUTHOR]

Nanowire lasers are potential light sources that can be used in photonic integrated circuits (PICs) for inter‐chip optical communication. However, due to the size incompatibility between a nanoscale laser and a micrometer‐scale optical waveguide, their integration within a PIC remains challenging. Here, an in situ growth strategy to directly construct perovskite nanolasers inside the long polymethyl methacrylate (PMMA) fibers is explored. As the perovskite nanolasers are embedded inside the PMMA fibers, effective coupling of lasing light to the PMMA fibers is expected. Furthermore, due to the protection of PMMA coating, the perovskite nanolasers exhibit high robustness in water and demonstrate significant improvement in photostability. Stable single‐mode and polarization operations are obtained at room temperature from the lasers with a low excitation threshold. Hence, these results pave the way to realize ultra‐stable perovskite‐based PICs suitable for inter‐chip optical communication. [ABSTRACT FROM AUTHOR]

Organic room‐temperature long‐persistent luminescent materials are promising light‐emitting materials for encryption, architectural decoration, organic solar cells, and biomedical applications. However, their unstable structures and thermal‐ and humidity‐induced emission quenching have greatly limited their utility and reliability. Here, we report a metal‐free nonconjugated copolymer that possesses stable photoluminescence at both high temperature and humidity. The room‐temperature long‐persistent luminescence (LPL) of this copolymer lasts for more than 15 s and can be recovered in high humidity conditions by heating to remove moisture. Copolymer LPL can be achieved with various excitation wavelengths, ranging from ultraviolet to near‐infrared, and the LPL color can be adjusted accordingly. The high initial LPL intensity and ultrafast filling time of the copolymer makes it suitable for low flicker alternating current‐driven light‐emitting diodes (AC‐LEDs). [ABSTRACT FROM AUTHOR]

Different from single coal seam mining, the stress evolution in the end mining stage of close‐distance coal seams is extremely complex. The unreasonable position and support of the lower retracement channel will cause serious deformation and damage to the surrounding rock. Taking the Yanzishan coal mine as the engineering background, the deformation and failure characteristics of the retracement channel under different overlay environments and the key influencing factors of position design were discussed by numerical simulation, theoretical analysis, and field investigation. The results show that the coupling superposition of upper coal pillar high stress and mining dynamic pressure will form a dangerous area with severe ground pressure behavior. The retracement channel should be preferentially designed in zone A (overlying mining roadways), followed by zone B (overlying end‐mining coal pillar), and finally, zone C (overlying section coal pillar). In addition, the rational horizontal distance between the lower retracement channel and the upper end‐mining coal pillar should make the channel in a good stress environment. The safety distance between the retracement channel and the nearest main roadway (end‐mining coal pillar width) should be greater than the severe range of advance abutment pressure. Finally, the design principle and control strategy for the lower retracement channel is proposed. The feasibility and rationality of the study are verified by industrial applications. [ABSTRACT FROM AUTHOR]

A latent image of the target after the X‐ray irradiation induced via a 980 nm laser or thermal excitation provides great potentials for healthcare diagnostics and nondestructive inspection. Taking the advantage of X‐ray time‐lapse imaging, simplified facilities and visualized information can be achieved. However, information acquisition with higher resolution, combined with long‐term storage for the corresponding X‐ray images remains a challenge. Herein, Tb3+‐doped Ba2LaF7 nanocrystals (NCs) grown in situ and dispersed uniformly in an amorphous glass matrix is explored, which performs a fascinating X‐ray response for imaging with an impressive spatial resolution reaching 20.0 lp mm−1. Moreover, the as‐developed corresponding scintillators exhibit excellent optical storage capability upon X‐ray irradiation for the constructed deep traps, and a controllable release of the captured carriers induced by thermal disturbance, and 980 nm laser stimulation can be achieved. Notably, the imaging resolution is well preserved to be 20.0 lp mm−1 even recorded after 10 days. The as‐explored Ba2LaF7:Tb3+ NCs embedded within an amorphous matrix realize a feasible approach for a simplified X‐ray imaging system with high‐resolution information production. [ABSTRACT FROM AUTHOR]

Sm3+, Mn4+ co‐activated LaGaO3 phosphors, giving the characteristic emissions of orange and red emission simultaneously, were prepared by a solid‐state reaction. Their luminescence properties, energy transfer behavior, thermal stability, and ratiometric temperature sensing performance were investigated. Thanks to the inhibition of energy transfer between Sm3+ and Mn4+ ions at high temperature and the reconstruction of the traps, the distinct optical behavior of the involved activators dependent on the ambient temperature was evaluated. Anti‐thermal quenching performance of Sm3+ ions along with the emission declination of Mn4+ ions was observed. Hence, the optical thermometry characteristics of the resultant phosphor based on the fluorescent intensity ratio (orange/red) realize a recorded temperature sensitivity of 4.19% K−1 and 2.09% K−1. Moreover, the as‐explored film combined with the LaGaO3: Sm3+, Mn4+ phosphor is demonstrated to be a promising multi‐color optical thermometer. [ABSTRACT FROM AUTHOR]

Scintillators, as the core materials for X‐ray imaging, have received great attention in radiation detection, security inspection, and biomedical applications. However, the current single crystal and thin film scintillators have encountered several issues, such as high cost, insufficient stability, and uneven distribution, which undoubtedly limit the development of high‐quality X‐ray imaging. Herein, the Y3Al5O12:Ce3+ (YAG:Ce3+) transparent ceramics (TCs), which presented a high transmittance of 82% and a steady‐state light yield of 24 600 photons MeV−1, are prepared by the vacuum solid‐state reactive sintering method. The fabricated YAG:Ce3+ TCs exhibit X‐ray imaging with an excellent spatial resolution (≈34.7 lp mm−1). Moreover, because of the structural stability of YAG:Ce3+ TCs, long‐term stable work under X‐ray irradiation is realized successfully. This work indicates that the TC scintillators provide a new opportunity for the development of high‐quality X‐ray imaging. [ABSTRACT FROM AUTHOR]

The exploration of the high thermal stability near‐infrared (NIR) phosphors is significantly crucial for the development of plant lighting. However, NIR phosphors suffer from the poor chemical and thermal stability, which severely limits their long‐term operation. Here, the successful improvement of luminous intensity (149.5%) and thermal stability at 423 K of Zn3Ga2GeO8 (ZGGO): Cr3+ phosphors is achieved for the introduction of Al3+ ions into the host. The release of carriers in deep traps inhibits the emission loss for the thermal disturbance. Furthermore, an NIR light emitting diodes (LEDs) lamp is explored by combining the optimized Zn3Ga1.1675Al0.8GeO8: 0.0325Cr3+ phosphors with a commercial 460 nm blue chip, and the emission band can match well with the absorption bands of photosynthetic pigments and the phytochrome (PR and PFR) of plants. The explored LEDs lamp further determines the growth and the pheromone content of the involved plants for the participation of the NIR emission originated from Cr3+ ions. Our work provides a promising NIR lamp as plant light with improved thermal stability for long‐term operation. [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]

Scintillators, converting the absorbed high‐energy X‐ray photons into to visible ones, have been used in fields as medical diagnostics, radiation dosimetry, and security inspection. Commercial bulk scintillators generally suffer from time‐consuming production, high‐cost operation, and deteriorated performance especially exposed to humidity. Here, in situ precipitated CdS quantum dots (QDs) within the transparent glass matrix are achieved feasibly. The CdS QDs glass‐ceramic (GC) is explored to be a superior scintillator with an outstanding weather resistance. A profound radioluminescence behavior and long‐term (≈3600 s) stability under X‐ray irradiation of the scintillator with the dose rate of 1 mGyair s−1 are demonstrated. Moreover, the indirect X‐ray imaging of the CdS GC reaches excellent resolution of 10 lp mm−1. Furthermore, the damaged scintillator under a long‐term cumulative dose up to 288 Gyair is recovered via a subsequent thermal treatment. Herein, the explored scintillator of CdS GC executes a promising cost‐effective X‐ray imaging for long‐term operation of the corresponding optoelectronic devices. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite quantum dots (QDs) CsPbX3 (X = Cl, Br, and I) have recently emerged as a new promising class of X‐ray scintillators. However, the instability of perovskite QDs and the strong optical scattering of the thick opaque QD scintillator film imped it to realize high‐quality and robust X‐ray image. Herein, the europium (Eu) doped CsPbBr3 QDs are in situ grown inside transparent amorphous matrix to form glass‐ceramic (GC) scintillator with glass phase serving as both matrix and encapsulation for the perovskite QD scintillators. The small amount of Eu dopant optimizes the crystallization of CsPbBr3 QDs and makes their distribution more uniform in the glass matrix, which can significantly reduce the light scattering and also enhance the photoluminescence emission of CsPbBr3 QDs. As a result, a remarkably high spatial resolution of 15.0 lp mm−1 is realized thanks to the reduced light scattering, which is so far a record resolution for perovskite scintillator based X‐ray imaging, and the scintillation stability is also significantly improved compared to the bare perovskite QD scintillators. Those results provide an effective platform particularly for the emerging perovskite nanocrystal scintillators to reduce light scattering and improve radiation hardness. [ABSTRACT FROM AUTHOR]

Environmental friendly metal halides have become emerging candidates as energy downconverting emitters for lighting and X‐ray imaging applications. Herein, luminescent single crystals of tetramethylammonium manganese chloride (C4H12NMnCl3) and tetraethylammonium bromide ((C8H20N)2MnBr4) are synthesized via a facile room‐temperature evaporation method. C4H12NMnCl3 and (C8H20N)2MnBr4 with octahedrally and tetrahedrally coordinated Mn2+ have correspondingly exhibited red and green emission peaking at 635 and 515 nm both originating from 4T1–6A1 transition of Mn2+ with high photoluminescence quantum yield (PLQY) of 91.8% and 85.1% benefiting from their specific crystal structures. Thanks to their strong photoexcitation under blue light, high PLQY, tunable emission spectra, good environmental stability, the white light‐emitting diode based on blending of C4H12NMnCl3 and (C8H20N)2MnBr4 delivers an outstanding luminous efficacy of 96 lm W−1, approaching commercial level, and shows no obvious photoluminescence intensity degradation after 3000 h under operation. In addition, manganese halides also demonstrate interesting characteristics under X‐ray excitation, C4H12NMnCl3 and (C8H20N)2MnBr4 exhibit steady‐state X‐ray light yields of 50 500 and 24 400 photons MeV−1, low detectable limits of 36.9 and 24.2 nGyair s−1, good radiation hardness, and X‐ray imaging demonstration with high‐resolution of 5 lp mm−1. This work presents a new avenue for luminescent Mn‐based metal halides toward multifunctional light‐emitting applications. [ABSTRACT FROM AUTHOR]

The advantages of ultrahigh photoluminescence quantum yield and narrow spectral bandwidth of all‐inorganic lead halide perovskite nanocrystals (NCs) enable them as the most potential candidates for optoelectronic applications. However, it is difficult to obtain long persistent luminescence from inorganic perovskite nanocrystals as the creation of effective trapping centers comes along with the generation of nonradioactive recombination centers. Here, replacing Pb2+ by appropriate lanthanide ions (Ln3+) in CsPbBr3nanocrystals that are embedded inside an amorphous transparent medium via a high‐temperature (≈500 °C) fabrication process is proposed to achieve stable and effective trapping centers. Furthermore, the surface coating of the enclosed nanocrystals prevents the formation of surface defects, leading to long persistent luminescence from CsPbBr3: Ln3+ NCs. The CsPbBr3: Ln3+ NCs with unprecedented high color purity (≈89.9%) and long lasting time of more than 1800 s could be a promising candidate for the application in anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Fluoride phase separation is the initial stage of nanocrystallization in oxyfluoride glasses, and it is a key step in achieving transparent glass‐ceramics with good luminescence. In this work, we combine molecular dynamics (MD) simulations and experimental studies to investigate the phase separation, nanocrystallization and photoluminescence in fluoroaluminosilicate glass and glass‐ceramics containing alkali earth fluoride (MF2). The results reveal different phase separation behaviors due to the field strength difference of M2+. The composition and size similarity between the fluoride‐rich regions in the MD simulated glass and the fluoride nanocrystals in the experimental prepared glass‐ceramics are observed, suggesting that the separated fluoride phase is the structural origin of the observed MF2 nanocrystals. Besides, in order to understand the M2+ dependent glass structural features, the crystallization temperatures, the luminescent properties of Eu3+ and Eu2+ doped glass‐ceramics, and the lasing performance of Er3+ doped glass‐ceramics are discussed. Based on these comprehensions, some strategies are proposed to help to efficiently design oxyfluoride glass with desired luminescence performance. [ABSTRACT FROM AUTHOR]

High energy ultraviolet (UV) and blue light (short wavelength) radiation is proved to be harmful to human eyes, skin, and biological genomes. However, developing effective shielding materials providing protect from short wavelength is still a great challenge. Here, Eu3+‐doped CsPbBr3 embedded in a transparent glass medium is proved to shield the short wavelength from 200 to 475 nm with high performance, which is prepared by a facile and efficient melting‐quenching technique. The uniform distribution of the CsPbBr3 quantum dots (QDs) growth in situ from the transparent glass matrix ensures the high transmittance (>90%) at the long wavelength (520‐800 nm). In addition, the excellent short wavelength shielding ability of the Eu3+‐doped CsPbBr3 glass ceramics (EGC) is demonstrated even suffered with accelerated weathering tests as long as 480 hours. Moreover the cell viability of A549 cells is well preserved thanks to the completely blocked blue light by the as‐obtained EGC, which unambiguously demonstrates the promising application of EGC as short wavelength shielding materials. [ABSTRACT FROM AUTHOR]

Fluorescent anti‐counterfeiting technologies have become indispensable by virtue of their high concealment properties. In this work, the observation of the characteristic emission originated from Eu2+ and Eu3+ ions in CaYAl3O7 realizes a dual‐mode anti‐counterfeiting strategy. The host matrix provides an environment, where blue and red emission could be manipulated with the introduction of Nd3+ ions for the reduced occupation of Eu3+ in the sites of Y3+ ions. Moreover, the photoluminescence spectra of these samples exhibit time and temperature‐dependent dynamic changes thanks to the capture and release of carriers in the reconstructed traps induced by Nd3+ ions. Herein, a multi‐stimuli responsive dynamic and static anti‐counterfeiting could be achieved in this work. [ABSTRACT FROM AUTHOR]

Lanthanide‐doped upconversion nanoparticles (UCNPs) have significant applications for single‐molecule probes and high‐resolution display. However, one of their major hurdles is the weak luminescence, and this remains a grand challenge to achieve at the single‐particle level. Here, 484‐fold luminescence enhancement in LuF3:Yb3+, Er3+ rhombic flake UCNPs is achieved, thanks to the Yb3+‐mediated local photothermal effect, and their original morphology, size, and good dispersibility are well preserved. These data show that the surface atomic structure of UCNPs as well as transfer from amorphous to ordered crystal structure is modulated by making use of the local photothermal conversion that is generated by the directional absorption of 980 nm light by Yb3+ ions. The confocal luminescence images obtained by super‐resolution stimulated emission depletion also show the great enhancement of individual LuF3:Yb3+, Er3+ nanoparticles; the high signal‐to‐noise ratio images indicate that the laser treatment technology opens the door for single particle imaging and practical application. [ABSTRACT FROM AUTHOR]

Abstract: The thermal quenching properties and mechanisms of phosphors employed in white light emitting diodes (wLEDs) are critical for their commercial application. Here, we attempted to characterize the deep traps for capturing and releasing carriers to improve the thermal stability of the blue‐emitting CaAl2O4: Eu2+, Tm3+ phosphors. The enhanced thermal stability contributed to the introduction of traps has been demonstrated, and the mechanism of the transport process of carriers, has been explored in detail. In comparison with Eu2+ doped sample, the co‐doped Tm3+ samples bring more deep traps. The releasing of carriers in deep traps therefore sustains the luminescence with increasing temperature and compensates the thermal luminescence intensity loss. The results provide a theoretical basis and new field of view for exploring excellent thermal stability phosphors for wLEDs. [ABSTRACT FROM AUTHOR]

Abstract: Acting as the electron trap, oxygen vacancies can strongly influence the long persistent luminescence (LPL) properties were verified in Ca2Ga2GeO7: Zn2+ (CGGZ) phosphor. The existence of oxygen vacancies in this self‐excitation material was confirmed by a simple fluorescence probe method. The introduction of zinc ions promotes the generation of oxygen vacancies, as well as optimizes its LPL properties. Thermoluminescence (TL) analysis revealed that electrons in deep trap will effectively transfer to the shallow one via the bridge of interstitial zinc. Accordingly, a mechanism for PL and LPL in this Gallogermanates was provided. [ABSTRACT FROM AUTHOR]

Abstract: Yb/Er doped hexagonal β‐NaLnF4 (Ln = Gd, Y, Lu) are regarded as the most efficient green upconversion (UC) materials. Unfortunately, β‐NaLnF4 is quite difficult to grow as monocrystal owing to cubic‐to‐hexagonal phase transition during cooling. As an alternative, herein a nanocrystallization controllable strategy to synthesize monodisperse whole‐family β‐NaLnF4 (from NaLaF4 to NaLuF4) embedded bulky glass ceramics is reported. A series of structural and spectroscopic characterizations indicate that Na content and Al/Si ratio are the most important factors to determine phase‐selective NaLnF4 crystallization in the aluminosilicate oxyfluoride glasses. Impressively, such nanocomposites are evidenced to be ideal hosts for upconversion luminescence of Yb3+/Er3+ dopants and as the proof‐of‐concept experiments, their applications in a random laser and incoherent LED‐excitable upconverting device as emitting media are demonstrated. It is expected that this study will provide a deep understanding for controllable crystallization in glass and extend the practical applications of glass ceramics in optoelectronic fields. [ABSTRACT FROM AUTHOR]

Abstract: Photoluminescence of CH3NH3PbCl3 single crystals under multiphoton excitation is studied. The emission intensity and wavelength, which are related to the phase of the single crystals, are found to be dependent on the operating temperature and pressure. High optical gain (>110 cm−1 @ ≈395 nm) and high absorption coefficient (≈9 × 10−10 cm9 GW−5 @ 2400 nm) can also be obtained from the single crystals. With suitable design of the resonant optical amplification, lasing emission at ≈395 nm is demonstrated from the single‐crystal microcavities under 2400 nm excitation. Hence, it is verified that CH3NH3PbCl3 single crystals can offer new opportunities for novel nonlinear photonics applications. [ABSTRACT FROM AUTHOR]