The historical development of lithium metal batteries is briefly introduced.• General strategies for protection of Li metal anodes are reviewed. • Specific challenges of ASSBs, Li-S and Li-air batteries are extensively discussed.• Current development status is reviewed and compared to the EU SET Plan targets.

Carbon black (CB) additives commonly used to increase the electrical conductivity of electrodes in Li-ion batteries are generally believed to be electrochemically inert additives in cathodes. Decomposition of electrolyte in the surface region of CB in Li-ion cells at high voltages up to 4.9 V is here studied using electrochemical measurements as well as structural and surface characterizations. LiPF 6 and LiClO 4 dissolved in ethylene carbonate:diethylene carbonate (1:1) were used as the electrolyte to study irreversible charge capacity of CB cathodes when cycled between 4.9 V and 2.5 V. Synchrotron-based soft X-ray photoelectron spectroscopy (SOXPES) results revealed spontaneous partial decomposition of the electrolytes on the CB electrode, without applying external current or voltage. Depth profile analysis of the electrolyte/cathode interphase indicated that the concentration of decomposed species is highest at the outermost surface of the CB. It is concluded that carboxylate and carbonate bonds (originating from solvent decomposition) and LiF (when LiPF 6 was used) take part in the formation of the decomposed species. Electrochemical impedance spectroscopy measurements and transmission electron microscopy results, however, did not show formation of a dense surface layer on CB particles. The growth of earth's population with concomitant increase in energy consumption require development of renewable energy conversion technologies coupled with advanced energy storage systems like lithium batteries.1,2 In order to increase the power density in Li-ion batteries, much research is focused on developing cathode materials that can operate at high voltages (above 4.5 V vs. Li/Li + ) with a high capacity, high cycling stability, and good rate capability.3-5 However, at high voltages, all the components of positive electrodes including the Al current collector, polymer binders, conductive additives, and other possible additives have an increased risk of degradation. In addition, one of the main issues with high voltage batteries is the instability of common aprotic electrolytes at voltage above 4.5 V. 6,7 The stability of the electrolyte/cathode interphase is related to the chemistry of electrolyte solvents and salts and also to the chemistry of the components of the cathode.Carbon black (CB) additives are one of the main constituents of cathodes, added to increase the electrical percolation and thus the electronic conductivity. 8,9 Though the weight percentage of CB in commercial batteries is generally very small, it composes a rather large part of the internal surface area of a cathode due to its small particle size (≈50 nm), low density, and high surface area. CBs are generally thought of being an electrochemically inert additive in cathodes, but few studies have investigated the role of CBs at high voltages and have indicated that CBs exhibit irreversible electrochemical reactions resulting in appreciable irreversible charge capacities. [10][11][12][13][14][15][16][17][18] This charge capacity is attributed to oxid...

Beta-nicotinamide adenine dinucleotide (NAD(+)) and its reduced form (NADH) play major roles in the development of electrochemical enzyme biosensors and biofuel cells. Unfortunately, the oxidation of NADH at carbon electrodes suffers from passivation of the electrodes and a decrease in passing currents. Here, we investigate experimentally and theoretically the reasons for such passivation. High-resolution X-ray photoelectron spectroscopy (HR-XPS), voltammetry, and amperometry show that adsorption occurs on the edges and "edge-like" defects of graphene sheets. HR-XPS and ab initio molecular dynamics show that the adsorption of NAD(+) molecules on the edges of graphene happens due to interaction with oxygen-containing groups such as carboxylic groups, while graphene edges substituted only with hydrogen are prone to passivation.

Density functional theory calculations predict two orientations for ellipsoidal C70 fullerenes inside single-walled carbon nanotubes (SWNTs) of different sizes: transverse orientation for C70 in (11,11) nanotubes (d=14.9 Å) and longitudinal orientation for C70 in (10,10) nanotubes (d=13.6 Å). SWNTs with these diameters have been prepared and filled with the C70 fullerenes, and characterized by Raman spectroscopy and high-resolution transmission electron microscopy, showing the orientations predicted by theory.

We present an optical to near-infrared selected astronomical catalogue covering 1270 deg. 2 . This is the first attempt to systematically combine data from 23 of the premier extragalactic survey fields -the product of a vast investment of telescope time. The fields are those imaged by the Herschel Space Observatory which form the Herschel Extragalactic Legacy Project (HELP). Our catalogue of 170 million objects is constructed by a positional cross match of 51 public surveys. This high resolution optical, near-infrared, and mid-infrared catalogue is designed for photometric redshift estimation, extraction of fluxes in lower resolution far-infrared maps, and spectral energy distribution modelling. It collates, standardises, and provides value added derived quantities including corrected aperture magnitudes and astrometry correction over the Herschel extragalactic wide fields for the first time. grizy fluxes are available on all fields with g band data reaching 5σ point-source depths in a 2 arcsec aperture of 23.5, 24.4, and 24.6 (AB) mag at the 25th, 50th, and 75th percentiles, by area covered, across all HELP fields. It has K or K s coverage over 1146 deg. 2 with depth percentiles of 20.2, 20.4, and 21.0 mag respectively. The IRAC Ch 1 band is available over 273 deg. 2 with depth percentiles of 17.7, 21.4, and 22.2 mag respectively. This paper defines the "masterlist" objects for the first data release (DR1) of HELP. This large sample of standardised total and corrected aperture fluxes, uniform quality flags, and completeness measures provides large well understood statistical samples over the full Herschel extragalactic sky.

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First principles molecular dynamics simulations of an aqueous solution salt system at finite concentration containing both Na(+) and Cl(-) ions show that a change in the distribution of the molecular dipole moment of H(2)O monomers appears when ions are present in solution. Simulations suggest a lowering of the dipole moments of the water molecules in the solvation shells of Na(+) and Cl(-) as compared to the pure water case, while the dipoles of the rest of the molecules are hardly affected. However, finer analysis in terms of the Wannier centers distribution suggests a change in the electronic structure of the water molecules even in the bulk. Also a change of the H-bond network arrangement was found and correlation between dipole and MOH parameter evidences such subtle effects, suggesting a lowering of tetrahedral order in salty solutions. All these changes can be related to observable quantities such as the infrared spectra thus allowing for a rationalization of the experimental outcome on neutral aqueous solutions.