Exploring hybrid Mg2+/H+ reactions of C@MgMnSiO4 with boosted voltage in magnesium-ion batteries

MgMnSiO4 is a promising cathode material for rechargeable magnesium batteries, however, it still suffers from unsatisfactory electrochemical performances. Although the modulation of electrolyte formulation and cell configuration are critical to enhancing the electrochemical behavior of MgMnSiO4, few works focused on these important issues. Therefore, to get cathode materials operating at high voltage and overcome the electrostatics problems of bivalent Mg2+ ion, we adopt an unconventional approach of engaging water in a conventional nonaqueous solution such as 0.5 M Mg(TFSI)2 in DME (dimethoxyethane). The electrochemical reaction of Mg/electrolyte/C@MgMnSiO4 cell occurs at 2.8 – 0.5 V (vs. Mg2+/Mg) with 160 mA h g-1 entailing 300 W h kg−1 at the materials’ level. The results show that C@MgMnSiO4 could be a potential cathode material for high-energy magnesium secondary batteries in a bifunctional electrolytes, which not just utilized as a transmitter ... of Mg2+, but also as a source of H+. We prove that the generated H+ increases the isotropy around Mg2+, changes in the Mn oxidation states, and modifies Mg/MgO interphase. Eventually, by assembling several Mg-ion full cells versus different anodes including Li4Ti5O12, activated carbon, and Mg0.5MnSiO4, we recall the main challenges to overcome

Quantitatively analyzing the failure processes of rechargeable Li metal batteries.

Practical use of lithium (Li) metal for high–energy density lithium metal batteries has been prevented by the continuous formation of Li dendrites, electrochemically isolated Li metal, and the irreversible formation of solid electrolyte interphases (SEIs). Differentiating and quantifying these inactive Li species are key to understand the failure mode. Here, using operando nuclear magnetic resonance (NMR) spectroscopy together with ex situ titration gas chromatography (TGC) and mass spectrometry titration (MST) techniques, we established a solid foundation for quantifying the evolution of dead Li metal and SEI separately. The existence of LiH is identified, which causes deviation in the quantification results of dead Li metal obtained by these three techniques. The formation of inactive Li under various operating conditions has been studied quantitatively, which revealed a general “two-stage” failure process for the Li metal. The combined techniques presented here establish a benchmark to unravel the complex failure mechanism of Li metal

Fabricated AIE-Based Probe to Detect the Resistance to Anoikis of Cancer Cells Detached from Tumor Tissue

(1) Background: Resisting anoikis is a vital and necessary characteristic of malignant cancer cells, but there is no existing quantification method. Herein, a sensitive probe for assessing anoikis resistance of cancer cells detached from the extracellular matrix was developed based on the aggregation-induced emission (AIE) of AIEgens. It has been reported that detached cancer cell endocytose activated integrin clusters, and in the endosome these clusters recruit and activate phosphorylate focal adhesion kinase (pFAK) in the cytoplasm to induce signaling that supports the growth of detached cancer cells. (2) Methods: We established a lost nest cell model of cancer cells and determined their ability to resist anoikis. The colocalization of the activated integrin, pFAK, and endosomes in model cells was observed and calculated. (3) Results: The fluorescence signal intensity of the probe was significantly higher than that of the integrin antibody in the model cells and the fluorescence signal of probe signal was better overlapped with labeled pFAK by fluorescence in endosomes in model cells. (4) Conclusions: We developed a quantitative multi-parametric image analysis program to calculate fluorescent intensity of the probe and antibodies against pFAK and Rab5 in the areas of colocalization. A positive correlation of fluorescence signal intensity between the probe and pFAK on the endosome was observed. Therefore, the probe was used to quantitatively evaluate resisting anoikis of different cancer cell lines under the lost nest condition

Olivine-Type MgMn0.5Zn0.5SiO4 Cathode for Mg-Batteries: Experimental Studies and First Principles Calculations

Magnesium driven reaction in olivine-type MgMn0.5Zn0.5SiO4 structure is subject of study by experimental tests and density functional theory (DFT) calculations. The partial replacement of Mn in Oh sites by other divalent metal such as Zn to get MgMn0.5Zn0.5SiO4 cathode is successfully developed by a simple sol–gel method. Its comparison with the well-known MgMnSiO4 olivine-type structure with (Mg)M1(Mn)M2SiO4 cations distribution serves as the basis of this study to understand the structure, and the magnesium extraction/insertion properties of novel olivine-type (Mg)M1(Mn0.5Zn0.5)M2SiO4 composition. This work foresees to extend the study to others divalent elements in olivine-type (Mg)M1(Mn0.5M0.5)M2SiO4 structure with M = Fe, Ca, Mg, and Ni by DFT calculations. The obtained results indicate that the energy density can be attuned between 520 and 440 W h kg−1 based on two properties of atomic weight and redox chemistry. The presented results commit to open new paths toward development of cathodes materials for Mg batteries

Solid‐State NMR and MRI Spectroscopy for Li/Na Batteries: Materials, Interface, and In Situ Characterization

Enhancing the electrochemical performance of batteries, including the lifespan, energy, and power densities, is an everlasting quest for the rechargeable battery community. However, the dynamic and coupled (electro)chemical processes that occur in the electrode materials as well as at the electrode/electrolyte interfaces complicate the investigation of their working and decay mechanisms. Herein, the recent developments and applications of solid-state nuclear magnetic resonance (ssNMR) and magnetic resonance imaging (MRI) techniques in Li/Na batteries are reviewed. Several typical cases including the applications of NMR spectroscopy for the investigation of the pristine structure and the dynamic structural evolution of materials are first emphasized. The NMR applications in analyzing the solid electrolyte interfaces (SEI) on the electrode are further concluded, involving the identification of SEI components and investigation of ionic motion through the interfaces. Beyond, the new development of in situ NMR and MRI techniques are highlighted, including their advantages, challenges, applications and the design principle of in situ cell. In the end, a prospect about how to use ssNMR in battery research from the perspectives of materials, interface, and in situ NMR, aiming at obtaining deeper insight of batteries with the assistance of ssNMR is represented

Sera from Breakthrough Infections with SARS-CoV-2 BA.5 or BF.7 Showed Lower Neutralization Activity against XBB.1.5 and CH.1.1

AbstractFrom December 2022 to January 2023, SARS-CoV-2 infections caused by BA.5 and BF.7 subvariants of B.1.1.529 (Omicron) spread in China. It is urgently needed to evaluate the protective immune responses in the infected individuals against the current circulating variants to predict the future potential infection waves, such as the BQ.1.1, XBB.1.5, and CH1.1 variants. In this study, we constructed a panel of pseudotyped viruses for SARS-CoV-2 for the past and current circulating variants, including D614G, Delta, BA.1, BA.5, BF.7, BQ.1.1, XBB.1.5 and CH.1.1. We investigated the neutralization sensitivity of these pseudotyped viruses to sera from individuals who had BA.5 or BF.7 breakthrough infections in the infection wave of last December in China. The mean neutralization ID50 against infected variants BA.5 and BF.7 are 533 and 444, respectively. The highest neutralizing antibody level was observed when tested against the D614G strain, with the ID50 of 742, which is about 1.52-folds higher than that against the BA.5/BF.7 variant. The ID50 for BA.1, Delta and BQ.1.1 pseudotyped viruses were about 2-3 folds lower when compared to BA.5/BF.7. The neutralization activities of these serum samples against XBB.1.5 and CH.1.1 decreased 7.39-folds and 15.25-folds when compared to that against BA.5/BF.7. The immune escape capacity of these two variants might predict new infection waves in future when the neutralizing antibody levels decrease furtherly