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3D metal halide perovskite X‐ray detectors have become the focus of research in recent years due to their superior sensitivity. However, the reported efficient perovskite X‐ray detectors all contain highly toxic lead and worrisome stability, which greatly limits their wide application and promotion. In this study, a distorted 3D germanium perovskite MAGeI3 single crystal (SC) is designed and grown by gradient cooling method. Due to its distorted octahedral structure, the MAGeI3 SCs not only possess high sensitivity but also have superior long‐term working stability. Specifically, the MAGeI3 SC X‐ray detectors achieve a record sensitivity of 42825 µC Gy−1 cm−2 and an impressive low detection limit of 4.1 nGy s−1, both of them are far better than the state‐of‐the‐art lead‐free perovskite SC X‐ray detectors. Moreover, the unencapsulated SC detector still maintains the original response even at high applied electric field and high dose rate X‐ray irradiation for several hours. Eventually, a high resolution of 7.2 lp mm−1 in X‐ray imaging is demonstrated on the MAGeI3 SC detector under a low dose rate of 478 nGy s−1 and at a low electric field of 1 V mm−1. This work provides a new pathway to design high‐performance and low‐toxicity X‐ray detectors. [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]

Summary: Bacterial wilt, caused by the Ralstonia solanacearum, can infect several economically important crops. However, the management strategies available to control this disease are limited. Plant growth‐promoting rhizobacteria (PGPR) have been considered promising biocontrol agents. In this study, Bacillus amyloliquefaciens strain Cas02 was isolated from the rhizosphere soil of healthy tobacco plants and evaluated for its effect on plant growth promotion and bacterial wilt suppression. Strain Cas02 exhibited several growth‐promoting–related features including siderophore production, cellulase activity, protease activity, ammonia production and catalase activity. Moreover, strain Cas02 showed a significant inhibitory growth effect on R. solanacearum, and its active substances were separated and identified to be macrolactin A and macrolactin W by HPLC‐DAD‐ESI‐MS/MS. Both greenhouse and field experiments demonstrated a good performance of Cas02 in plant growth promotion and bacterial wilt suppression. To explore the underlying genetic mechanisms, complete genome sequencing was performed and the gene clusters responsible for antibacterial metabolites expression were identified. Overall, these findings suggest that the strain Cas02 could be a potential biocontrol agent in bacterial wilt management and a source of antimicrobial compounds for further exploitation. [ABSTRACT FROM AUTHOR]

Lead halide perovskites with good optoelectronic properties and high attenuation of high-energy radiation are great candidates for X-ray radiation detectors. Large area, dense, and thick films or wafers are a prerequisite for these applications. In this paper, a one-step heat-assisted high-pressure press method is developed to directly prepare a large (the largest has a diameter of 80 mm) and thickness- and shape-controlled phase-pure organic-inorganic hybrid CH 3 NH 3 PbI 3 wafer of densely packed large microcrystals from raw powder materials. Meanwhile, this method uses no solvent to achieve essentially 100% material utilization. The obtained wafers show good ambipolar carrier mobilities of ∼20 cm 2 V -1 s -1 and a μτ product as high as 3.84 × 10 -4 cm 2 V -1 . Under an X-ray source using an acceleration voltage of 40 kV, the perovskite wafer-based X-ray detector shows an X-ray sensitivity as large as 1.22 × 10 5 μC Gy air -1 cm -2 under a 10 V bias, the highest reported for any perovskite material. The method provides a convenient strategy for producing large perovskite wafers with good optoelectronic properties, which will facilitate the development of large perovskite devices.