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CsPbBr3 nanoplates (NPs) have shown great potential in diverse optoelectronic applications. Despite the wonderful luminescence properties, the inherent instability of these NPs hinders their use in practical situations. Herein, a facile water‐assisted strategy is reported to synthesize highly stable blue emission CsPbBr3 NPs encapsulated in PbBr(OH). The introduction of water directly into the reaction mixture is pivotal, as it triggers the transformation of bulk CsPbBr3 nanocubes into 2‐D CsPbBr3 NPs within the PbBr(OH) matrix, resulting in the formation of CsPbBr3@PbBr(OH) microbricks. Remarkably, the water content in the reaction mixture allows the control of the number of perovskite layers in the NPs, thus enabling the emission color to be tuned from deep blue to green. The unconventional approach presented herein not only offers a cost‐effective pathway to synthesize blue‐emitting perovskites which are highly stable in a wide variety of polar and non‐polar solvents, but also holds immense potential for propelling the advancement of high‐performance LEDs and other optoelectronic devices. The findings underscore the significance of water in dictating the growth dynamics and emission characteristics of perovskite NPs, paving the way for their practical application. [ABSTRACT FROM AUTHOR]

Quantum‐confined perovskite CsPbBr3 Nanoplatelets (NPLs) have recently emerged as promising blue‐emitting materials for perovskite light‐emitting diodes (PeLEDs). Yet, their susceptibility to optical instability in solid films under ambient conditions poses a significant hindrance. This study introduces a novel chelating strategy that utilizes metal manganese ions and multidentate ligands, markedly improving the structural stability, and emission efficiency of NPLs. The approach involves adding Diethylenetriaminepentaacetic acid (DTPA) to the perovskite precursor solution, which allows for strong coordination to surface [PbBr6]4− octahedrons via its multiple chelation sites. Ensuing metal manganese ion integration during the purification phase addresses Pb2+ and Br− site vacancies, culminating in near‐perfect octahedral structures with significantly fewer vacancies. These metal manganese ions are then further immobilized on the NPLs surface by the chelating effect of unbound DTPA functional groups. The resultant CsPbBr3 NPLs films demonstrate an impressive PLQY of 66%, showcasing remarkable air stability with consistent blue emission for up to 5 days. The CsPbBr3 NPLs‐based PeLEDs show electroluminescence at 460 nm with a current efficiency of 1.07 cd A−1 and a maximum luminance of 220 cd m−2. The proposed chelating strategy positions perovskite NPLs as an extremely promising prospect in future applications of high‐definition displays and high‐quality lighting. [ABSTRACT FROM AUTHOR]

CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) have shown great potential in numerous applications including wide color gamut display and lighting. Despite the wonderful luminescence properties, the inherent instability of these NCs hinders their use in practical situations. Herein, we report a facile aqueous-based, ligand-free method to synthesize highly stable CsPbX3 NCs using ZIF-62, a metal–organic framework, as an encapsulation matrix which effectively isolates CsPbX3 from the surrounding. We discovered that the slightly alkaline nature of ZIF-62 facilitates the reaction between water and PbBr2 to form PbBr-(OH), which not only passivates the surface defects of the CsPbBr3 NCs but also prevents the perovskite from decomposing or oxidizing at high temperature. Sintering of ZIF-62 can therefore be performed in air at ∼300 °C to completely seal the perovskite within the insulating matrix, resulting in CsPbBr3/ZIF-62 composites exhibiting high stability against polar solvents, heat, light, and ambient humidity. Notably, the composite can maintain its bright luminescence without noticeable degradation in water for more than 2 months. The narrow-band emission and stability of these composites led to the demonstration of white light-emitting diodes with excellent color stability. Without the need for organic solvents during NC synthesis and noble gas ambient during sintering, the strategy proposed here can potentially facilitate the cost-effective, large-scale synthesis of highly stable perovskites which show great promise in commercial applications. [ABSTRACT FROM AUTHOR]

Here, we report the extraordinary electrochemical energy storage capability of NiMoO 4 @NiMoO 4 homogeneous hierarchical nanosheet-on-nanowire arrays (SOWAs), synthesized on nickel substrate by a two-stage hydrothermal process. Comparatively speaking, the SOWAs electrode displays superior electrochemical performances over the pure NiMoO 4 nanowire arrays. Such improvements can be ascribed to the characteristic homogeneous hierarchical structure, which not only effectively increases the active surface areas for fast charge transfer, but also reduces the electrode resistance significantly by eliminating the potential barrier at the nanowire/nanosheet junction, an issue usually seen in other reported heterogeneous architectures. We further evaluate the performances of the SOWAs by constructing an asymmetric hybrid supercapacitor (ASC) with the SOWAs and activated carbon (AC). The optimized ASC shows excellent electrochemical performances with 47.2 Wh/kg in energy density of 1.38 kW/kg at 0-1.2 V. Moreover, the specific capacity retention can be as high as 91.4% after 4000 cycles, illustrating the remarkable cycling stability of the NiMoO 4 @NiMoO 4 //AC ASC device. Our results show that this unique NiMoO 4 @NiMoO 4 SOWA has great prospects for future energy storage applications.

Objective: To explore the role of vascular endothelial growth factor C (VEGF-C), VEGFR-3 and nm23-H(1) in lymphatic metastasis of oral squamous cell carcinoma (OSCC)., Methods: The expression of VEGF-C, VEGFR-3 and nm23-H(1) were examined by immunohistochemical SP method. The lymphatic vessels density (LVD) in tumors was counted and analyzed with clinicopathologic parameters., Results: VEGF-C, LVD and nm23-H(1) expressions were significantly different between OSCC and benign and precancerous lesions (P < 0.05). VEGF-C was correlated with lymph node metastasis and LVD (P < 0.01). nm23-H(1) was related to clinical stage, histological grade and lymphatic metastasis (P < 0.05)., Conclusions: The high expressions of VEGF-C/VEGFR-3 and inactivation of nm23-H(1) may play an important role in lymphatic metastasis in OSCC.

Objective: To investigate the role of interleukin-18 (IL-18) and interferon-gamma (IFN-gamma) in coronary heart disease (CHD)., Methods: The levels of plasma IL-18 and IFN-gamma in 45 patients with CHD and 30 normal volunteers were determined by enzyme linked immunoadsorbent assay (ELISA). The correlation between the levels of these two cytokines and the relationship between their levels and the state of CHD were analyzed., Results: The plasma levels of IL-18 and IFN-gamma in patients with CHD were increased significantly when compared to those in normal controls [IL-18: (373.6+/-176.7) ng/L vs. (226.3+/-88.9) ng/L, P<0.01; IFN-gamma: (1.769+/-0.087) ng/L vs. (0.087+/-0.038) ng/L, P<0.01]. The two cytokines were positively correlated significantly (r=0.788, P<0.01)]. The plasma levels of IL-18 and IFN-gamma were significantly different in different states of CHD, and they increased with the aggravation of CHD respectively (all P<0.01). Moreover, the plasma levels of IL-18 and IFN-gamma in patients complicated with heart failure (HF) were higher than those not complicated with HF, respectively (all P<0.01)., Conclusion: The findings suggest that IL-18 and IFN-gamma may participate in the pathogenesis and progression of CHD. The plasma levels of two cytokines may be used as parameters of estimation the morbid state of CHD.