Anode‐free rechargeable lithium (Li) batteries (AFLBs) are phenomenal energy storage systems due to their significantly increased energy density and reduced cost relative to Li‐ion batteries, as well as ease of assembly because of the absence of an active (reactive) anode material. However, significant challenges, including Li dendrite growth and low cycling Coulombic efficiency (CE), have prevented their practical implementation. Here, an anode‐free rechargeable lithium battery based on a Cu||LiFePO4 cell structure with an extremely high CE (>99.8%) is reported for the first time. This results from the utilization of both an exceptionally stable electrolyte and optimized charge/discharge protocols, which minimize the corrosion of the in situly formed Li metal anode.

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Nanocomposite polymer electrolytes present new opportunities for rechargeable magnesium batteries. However, few polymer electrolytes have demonstrated reversible Mg deposition/dissolution and those that have still contain volatile liquids such as tetrahydrofuran (THF). In this work, we report a nanocomposite polymer electrolyte based on poly(ethylene

A fundamental understanding of electrochemical reaction pathways is critical to improving the performance of Li-S batteries, but few techniques can be used to directly identify and quantify the reaction species during disharge/charge cycling processes in real time. Here, an in situ (7)Li NMR technique employing a specially designed cylindrical microbattery was used to probe the transient electrochemical and chemical reactions occurring during the cycling of a Li-S system. In situ NMR provides real time, semiquantitative information related to the temporal evolution of lithium polysulfide allotropes during both discharge/charge processes. This technique uniquely reveals that the polysulfide redox reactions involve charged free radicals as intermediate species that are difficult to detect in ex situ NMR studies. Additionally, it also uncovers vital information about the (7)Li chemical environments during the electrochemical and parasitic reactions on the Li metal anode. These new molecular-level insights about transient species and the associated anode failure mechanism are crucial to delineating effective strategies to accelerate the development of Li-S battery technologies.

Supported VO x /TiO2-rod catalysts were studied by 51V MAS NMR at high field using a sample spinning rate of 55 kHz. The superior spectral resolution allows for the observation of at least five vanadate species. The assignment of these vanadate species was carried out by quantum chemical calculations of 51V NMR chemical shifts of model V surface structures. Methanol oxidative dehydrogenation (ODH) was used to establish a correlation between catalytic activity and the various surface V sites. It is found that monomeric V species are predominant at low vanadium loadings with two 51V NMR peaks observed at about −502 and −529 ppm. V dimers with two bridged oxygens result in a peak at about −555 ppm. Vanadate dimers and polyvanadates connected by one bridged oxygen atom between two adjacent V atoms resonate at about −630 ppm. A positive correlation is found between the V dimers, giving rise to the −555 ppm peak, and the ODH rate, and an even better correlation is obtained by including V monomer contributions. This result suggests that surface V dimers related to the −555 ppm peak and monomers are the primary active sites for the methanol ODH reaction. Furthermore, a portion of the V species is found to be invisible to NMR and the level of such invisibility increases with decreasing V loading levels, suggesting the existence of paramagnetic V species at the surface. These paramagnetic V species are also found to be much less active in methanol ODH.

Here we present the design of reusable and perfectly-sealed all-zircornia MAS rotors. The rotors are used to study AlPO4-5 molecular sieve crystallization under hydrothermal conditions, high temperature high pressure cyclohexanol dehydration reaction, and low temperature metabolomics of intact biological tissue.

c Similar to other positive-sense, single-stranded RNA viruses, hepatitis C virus (HCV) replicates its genome in a remodeled intracellular membranous structure known as the membranous web (MW). To date, the process of MW formation remains unclear. It is generally acknowledged that HCV nonstructural protein 4B (NS4B) can induce MW formation through interaction with the cytosolic endoplasmic reticulum (ER) membrane. Many host proteins, such as phosphatidylinositol 4-kinase III␣ (PI4KIII␣), have been identified as critical factors required for this process. We now report a new factor, the cytosolic phospholipase A2 gamma (PLA2G4C), which contributes to MW formation, HCV replication, and assembly. The PLA2G4C gene was identified as a host gene with upregulated expression upon HCV infection. Knockdown of PLA2G4C in HCV-infected cells or HCV repliconcontaining cells by small interfering RNA (siRNA) significantly suppressed HCV replication and assembly. In addition, the chemical inhibitor methyl arachidonyl fluorophosphonate (MAFP), which specifically inhibits PLA2, reduced HCV replication and assembly. Electron microscopy demonstrated that MW structure formation was defective after PLA2G4C knockdown in HCV replicon-containing cells. Further analysis by immunostaining and immunoprecipitation assays indicated that PLA2G4C colocalized with the HCV proteins NS4B and NS5A in cells infected with JFH-1 and interacted with NS4B. In addition, PLA2G4C was able to transport the HCV nonstructural proteins from replication sites to lipid droplets, the site for HCV assembly. These data suggest that PLA2G4C plays an important role in the HCV life cycle and might represent a potential target for anti-HCV therapy.