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Electrochemical, surface, and structuralstudies related to rechargeableMg batteries were carried out with monolithic thin-film cathodes comprisinglayered V2O5and MoO3. The reversibleintercalation reactions of these electrodes with Mg ion in nonaqueousMg salt solutions were explored using a variety of analytical tools.These included slow-scan rate cyclic voltammetry (SSCV), chrono-potentiometry(galvanostatic cycling), Raman and photoelectron spectroscopies, high-resolutionmicroscopy, and XRD. The V2O5electrodes exhibitedreversible Mg-ion intercalation at capacities around 150–180mAh g–1with 100% efficiency. A capacity of 220mAh g–1at >95% efficiency was obtained withMoO3electrodes. By applying the electrochemical drivingforcesufficiently slowly it was possible to measure the electrodes at equilibriumconditions and verify by spectroscopy, microscopy, and diffractometrythat these electrodes undergo fully reversible structural changesupon Mg-ion insertion/deinsertion cycling. [ABSTRACT FROM AUTHOR]

We examined a new Li-ion battery system based on the combination of a high voltage LiMn0.8Fe0.2PO4 (LMFP) cathode with a Li4Ti5O12 (LTO) anode. Due to the relatively high red-ox voltage of LTO (1.5 V vs. Li) and the excellent stability of its spinel structure, as well as the fact that the red-ox potential of a Li[MnFe]PO4 cathode, up to 4.1 V, does not endanger the anodic stability of a standard electrolyte solutions, it is assumed that such cells can be safe, stable, highly reversible, and suitable for load-leveling applications. The LMFP/LTO cells exhibited excellent rate capability and cycle life at 30°C, delivering discharge capacity of 153, 152, 146, and 118 mAhg-1 (cathode) at 0.1 C, C, 2 C, and 5 C rates. These cells demonstrated excellent high temperature performance when the LTO anodes were pre-passivated before cell operation. By XRD and ICP analyzes of C-LiMn0.8Fe0.2PO4 electrodes before and after charge/discharge cycles, the capacity fading of these systems at high temperatures was attributed to depletion of active Li from the electrodes, due to side reactions on the anode side. These were avoided by pre-passivation of the LTO electrodes. The surface chemistry of Li4Ti5O12 anodes was investigated with the anodic surface reactions arising mainly from the salt (LiPF6). [ABSTRACT FROM AUTHOR]

Si electrodes are the most important high capacity substitutes of Li metal and carbon anodes in high energy density Li ion batteries, including those based on sulfur or air cathodes. In this study we examined amorphous columnar structure silicon film anodes prepared by sputtering in rechargeable Li ion battery prototypes based on TiS2 cathodes. The choice of this cathode material enabled focusing on the examination of pre-lithiated Si films as anode candidates in alkyl carbonate electrolyte solutions. The effectiveness of fluoro-ethylene carbonate (FEC) as a co-solvent in alkyl carbonates/LiPF6 solutions for good performance of silicon anodes was exhibited. Hundreds of cycles were demonstrated in full Li ion cells containing these components. The columnar morphology of these anodes is retained after 1000 cycles. Their surface chemistry, measured by EDS and XPS is discussed. The results of this work encourage further R&D efforts toward the use of amorphous silicon films as anodes in advanced rechargeable Li batteries. [ABSTRACT FROM AUTHOR]

• Uranium and cerium containing samples were examined as part of an international nuclear forensics exercise. • The main technique for characterization was the combined analysis by SEM-EDS/Raman of the surface. • Connection between the ingots was determined by uranium and cerium isotopic ratios as well as yttria and graphite surface contaminations. • Sample preparation history was interpreted based on surface contaminations, showing multiple impurities present in suggested production and processing sites. The objective of this paper is to describe nuclear forensics material characterization, as conducted in the Israeli National Nuclear Forensic Laboratory (INNFL) during an international exercise Collaborative Material Exercise 6 (CMX6) organized by the Nuclear Forensics international technical working group (ITWG). The characterized materials are uranium and cerium metal ingots. The goal was characterization of physical parameters, elemental and isotopic composition, morphology and chemical composition of the surface. Electron microscopy and Raman spectroscopy techniques were combined for morphological, structural and elemental study of the surface. The information from these analyses was used to answer the exercise questions, comparing the materials (labeled ES-1 and ES-2) to each other and to other samples described in the scenario. The INNFL investigation identified a connection between ES-1 and ES-2 based on several indicators, including the isotopic composition of the uranium present in both samples, as well as other surface contaminations, mainly yttria and graphite. Based on these finding the INNFL established a connection between ES-1 and ES-2 to ES-3B (theoretical sample with uranium traces) and has not established a connection to ES-3A (theoretical sample of plutonium powder). ES1 and ES-2 have been suggestively connected to their theoretical source, by their isotopic ratio. The INNFL conclusion was that the theoretical source materials (oxide and fluoride) were converted into the actual materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Herein, we report energy storage devices, which are based on densely packed, vertically aligned MoS 2 (VA-MoS 2 ) or planar oriented MoS 2 (PO-MoS 2 ) and compare their electrochemical performances. The VA-MoS 2 films have been processed by chemical vapor deposition (CVD) to reach unprecedented micron-scale thick films while maintaining the vertical alignment for the whole thickness. The VA-MoS 2 and the PO-MoS 2 films form a high-performance Li-ion electrode, reaching the theoretical limits of reversible capacity for this material (800 mAh/g; twice the specific capacity of graphite). The vertical alignment allows faster charge-discharge rates while maintaining a high specific capacity (C-rate measurements). Noteworthy, the reversible cycling of the Li-ion electrode also benefits from the vertical alignment. In this article, we present the full synthesis, structural and electrochemical characterization of VA-MoS 2 along with the properties of PO-MoS 2 to deconvolute the intrinsic properties of MoS 2 from the influence of the layers' orientation.