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Burkholderia semiarida has only been reported as a plant pathogen causing onion sour skin (1). The Burkholderia genus encompasses >120 bacterial species that are typically reported to inhabit soil and [...]

High-quality and large-size crystals are ideal scintillation screens to achieve high-resolution X-ray imaging. However, it is difficult to obtain large-size scintillation crystals due to the limitations of crystal growth technology. Here, organic–inorganic hybrid Mn-based single crystals (TBP2MnBr4, TBP = tetrabutylphosphonium) exhibit a high decomposition temperature (295 °C) and the TBP2MnBr4-melt has a low condensation point (48.75 °C), such a wide interval is of benefit to the melt processing method for preparing scintillation screens. The TBP2MnBr4-melt exhibits a low viscosity (η(Tm) = 238 mPa s) and flow activation energy (Ea = 10.754 kJ mol−1) making it easy to crystallize. It is worth noting that the low condensation point (Tc) of the TBP2MnBr4-melt is slightly higher than room temperature, and this narrow temperature interval can limit the rapid nucleation and growth of the crystals, allowing them to slowly crystallize into transparent ceramics (TC). Circular TBP2MnBr4-TC with a size of Φ 11.5 cm can be easily fabricated, which exhibits high optical transmittance, for realizing high-resolution (16 lp mm−1) X-ray imaging. This work brings a new strategy for preparing scintillation screens, as well as promoting the development of TC scintillators for X-ray imaging. [ABSTRACT FROM AUTHOR]

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X‐ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I−) serve as the electron donor. The prepared butyl(2‐[2‐(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4‐I) exhibits bright blue emission and an ultra‐high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n‐π and anion‐π stacking in solid‐state C4‐I. Photophysical studies of C4‐I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near‐pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X‐ray attenuation ability endowed by I, C4‐I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s−1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X‐ray attenuation ability, and excellent scintillator performance. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive luminescent materials have attracted much research attention due to their wide application potential in various fields. Typically, the family of hydrated double perovskite A2MIIIX5·H2O shows unique emission color transformation between hydrated and dehydrated complexes, highlighting the application potential in advanced anti‐counterfeiting. Herein, two zero‐dimensional perovskites of Cs2YbCl5·H2O and Cs3YbCl6, are reported and broad‐band self‐trapped exciton recombination emission can be realized via external Sb3+ doping. Intriguingly, the Cs2YbCl5·H2O can be transformed to the dehydrated counterpart of Cs3YbCl6 through a facile methanol treatment at room temperature, leading to the emission color transformation from yellow to green. Notably, the green‐emissive Cs3YbCl6:Sb3+ delivers a high photoluminescence quantum yield of 67.3%. Leveraging the advantages of obvious methanol‐induced emission color transformation between Cs2YbCl5·H2O and Cs3YbCl6 at room temperature, Cs2YbCl5·H2O can be used in the field of high‐security‐level anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

The development of large‐area transparent organic‐inorganic hybrid metal halide (OIMH) scintillation screens is restricted by the anisotropic single‐crystal growth, numerous grain boundaries in polycrystalline wafers, and inhomogeneous dispersion in perovskite‐polymer composite films. The crystal‐glass phase transition of OIMH materials may provide a promising solution for the above significant challenges. Herein, a new class of transparent amorphous guanidinium‐based manganese bromide glasses, (DPG)2MnBr4 and (DOTG)2MnBr4 (DPG = 1,3‐diphenylguanidinium, DOTG = 1,3‐di‐o‐tolylguanidinium), are synthesized through a low‐temperature melt‐quenching process. The (DOTG)2MnBr4 shows impressive glass‐forming ability because of large viscosity (η) at the melting temperature (Tm) (η(Tm) = 3426 mPa·s) and small fragility index (m = 52.35), which can be a potential glass scintillator. The large‐area (e.g., 13 cm × 13 cm) transparent amorphous (DOTG)2MnBr4 glass scintillator shows high light transmittance of > 80%, a low detection limit of 237.3 nGy s−1 and high X‐ray imaging spatial resolution of 12 lp mm−1. Interestingly, the glass transition temperature of < 40 °C gives (DOTG)2MnBr4 glass unique thermoplastic properties, allowing it to conform to irregularly shaped objects and reduce the distortion in X‐ray imaging. [ABSTRACT FROM AUTHOR]

The current mainstream planar X‐ray imaging techniques face significant challenges for accurately capturing the internal structure of curved objects, since the variable distances between the curved objects and the flat‐panel scintillation screen cannot eliminate the distortion in X‐ray imaging. Though large‐area and transparent curved scintillation screens are much more desirable. Here, organic–inorganic hybrid Mn‐based single crystals ([CH3Ph3P]2MnX4, X = Cl, Br, I) exhibiting high photoluminescence quantum yield (PLQY) and low melting temperature have been employed to prepare transparent glass for X‐ray scintillation imaging application through a low‐temperature melting strategy. The [CH3Ph3P]2MnBr4‐glass shows high PLQY (47.8%), high‐resolution X‐ray imaging performance (12.3 lp mm−1), low limit of detection (25.33 nGy s−1), and impressive X‐ray irradiation stability (102 Gy). Furthermore, high‐contrast X‐ray imaging at a low dose (6.865 µGy per exposure, 14.5 times lower than the chest radiograph) is achieved. Based on the low glass transition temperature (Tg = 53.6 °C) and easy‐shapeable properties of [CH3Ph3P]2MnBr4‐glass scintillator, the large‐area curved scintillation screen with a series of sizes of Φ 2×4 – Φ 8×4 cm2 can be easily fabricated and show high X‐ray imaging quality. These findings provide a paradigm for future research in shapeable X‐ray scintillators, unlocking new possibilities for curved and 3D X‐ray imaging. [ABSTRACT FROM AUTHOR]

Single‐source white‐light emitters are highlighted with stable color and excellent color rendering ability, which can largely simplify the white‐light‐emitting‐diode (WLED) structure. All‐inorganic and lead‐free double perovskites have attracted extensive research interest and provide versatile doping sites to accommodate the extrinsic multi‐valent ions. Herein, the synthesis and tunable emission of Sb3+–Ln3+‐codoped Cs2NaYCl6 single crystals (SCs) is reported. Particularly, bright white‐light emission with a high photoluminescence quantum yield of 80.5% is yielded in 0.5%Sb3+–2%Tb3+–2%Sm3+‐codoped Cs2NaYCl6 SCs. Steady‐state photoluminescence (PL) and time‐resolved PL spectra are employed to reveal the energy transfer from Sb3+‐induced self‐trapped excitons to Ln3+ ions. Temperature‐dependent PL spectra further demonstrate that the fluorescence intensity ratio of band 657 to band 590 nm is highly dependent on the temperature, and the relative sensitivity reaches a maximum of up to 1.59% K−1 at 260 K. Moreover, the WLED based on 0.5%Sb3+‐2%Tb3+‐2%Sm3+‐codoped Cs2NaYCl6 SCs delivers a higher average color rendering index of 87 than 0.5%Sb3+‐0.8%Tb3+‐2.5%Ho3+‐codoped Cs2NaYCl6 (74.6). The outstanding white‐light‐emission performance together with the high temperature dependence of the fluorescence spectra confers Sb3+–Ln3+‐codoped Cs2NaYCl6 with huge application potential in solid‐state lighting and ratiometric optical thermometry. [ABSTRACT FROM AUTHOR]