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Li–O2 batteries can provide greater gravimetric energy than Li-ion batteries but suffer from poor efficiency and cycle life due to the instability of aprotic electrolytes. In this study, we show that the apparent four-electron oxygen reduction to form Li2O in Li–O2 batteries with molten nitrate is facilitated by the electrochemical reduction of nitrate to nitrite, and subsequent chemical oxidation of nitrite to nitrate by molecular oxygen, instead of a four-electron oxygen reduction aided by disproportionation of Li2O2 generated from two-electron reduction of molecular oxygen. By examining a series of transition metal catalysts using experiments and computation, optimizing the surface binding of nitrate to enhance the kinetics of the electrochemical reduction of nitrate to nitrite, as well as increasing the kinetics of nitrite oxidation by O2 was shown to increase the discharge voltage and render the observed high-rate capability for NiO-based surfaces in Li–O2 batteries.

To gain better insight into the influence of the anion size and symmetry on the transport properties and thermal stability of an electrolyte based on lithium (fluorosulfonyl)(trifluoromethanesulfonyl)-imide (FTFSI) salt, we performed the physical and electrochemical characterization of an electrolyte based on FTFSI incorporated in standard binary (3EC/7EMC) and ternary (EC/PC/3DMC) alkylcarbonate mixtures. By applying the Jones-Dole-Kaminsky (JDK), Eyring and Arrhenius empirical models to the electrolyte viscosity we show that the activation enthalpy and entropy energy barriers ( Δ H ≠ , Δ S ≠ ) for viscous flow are between 12 and 15 kJ·mol−1. They are strongly dependent on the solvent nature and are significantly lower than their symmetric anions LiFSI and LiTFSI (19–20 kJ·mol−1) in the binary mixture. Furthermore, the hydrodynamic radius, rs, calculated by JDK, and the ionicity behavior illustrated by the Walden role, showed that the FTFSI anion is outside the solvation sphere (rs > 0.6 nm) which is smaller in the case of an EC/EMC solvent base. In the 3EC/7EMC solvent mixture, LiFTFSI is less conductive than in the ternary mixture i.e., σmax = 8.9 mS cm−1 at Cmax = 1.1 mol L−1 for 3EC/7EMC and, σmax = 10.5 mS cm−1 at max = 0.7 mol L−1 for EC/PC/3DMC, due to a strong solvation and a greater association of FTFSI ions in the binary solvent mixture. The thermal stability of FTFSI based electrolytes was determined by the shift of the evaporation temperature of the volatile solvents (DMC, EMC) in the presence of salt, towards the higher temperatures. This feature is visible on the thermograms obtained by DSC both with the liquid electrolyte and with charged LMO cathodes in presence of electrolytes. The consequences of these properties on the electrochemical behavior of a graphite (Gr) half-cell, a lithium metal (Li) anode and a manganese lithium oxide (LMO) cathode demonstrated on the one hand the formation of a thick solid electrolyte interphase (SEI) on graphite that consumed a significant amount of lithium i.e., 18% of total capacity of the first charge. Furthermore, LiFTFSI delivered 95% of the initial capacity C = 360 mAh g−1 at C/10 with EC/PC/3DMC versus 91% when it was combined with 3EC/7EMC C = 348 mAh g−1, while the capacities obtained for LiTFSI in EC/PC/3DMC were the lowest (C = 275 mAh g−1) compared to those of the other salts. After 10 cycles, the capacity loss at C/20 is

In this study nano lithium oxide Li2O was prepared using simple chemical method SCM. Structural and optical invesitgations were executed such as X-ray diffraction XRD, Scanning Electron Microscopy SEM, Foriour Trandformation InfraRed FTIR and UV–Vis to know the characteristics of the nano material, then nano Li2O was deposited on p and n-types porous silicon substrates to fabricate the heterojunction after appliying Al drops on upper and lower side. Two applications of the manufactured heterojunction were carried out solar cell and measuring its characteristics and photodetector with its figures of merit.

One of the attempts to improve γ-alumina catalytic performance lies in the use of additives that prone to segregate on its interfaces. The catalytic activity depends on the acidity or basicity of the doping oxides. Li2O is one of these oxides that when is loaded on γ-alumina surface decreases the number of Lewis acid sites. However, little is known about the Li2O distribution in the γ-alumina structure and interfaces. Thus, a detailed study of the lithium oxide distribution in the nanostructure of γ-alumina is the aim of this study. Nanometric powders were synthesized by the polymeric precursor method. The nanopowders were doped with Li+ ions (0.1, 0.5, 1, 3, 5, and 10 mol%) followed by calcination at 650 °C and 750 °C for 15 h. The powders were characterized by XRD, XRF, FTIR-DRIFT, BET specific surface area (SSA) and helium pycnometry. The surface excess due to the lithium oxide segregation was determined by the selective lixiviation method which has proved to be effective in quantifying surface excess of segregated ions at oxide interfaces. The crystallite sizes of the nanopowders varied from 3.3 nm to 9.2 nm, while their SSA were between 82.0 m2/g to 119.9 m2/g. The chemical analyses suggest that the lithium segregates in the γ-alumina interfaces at 650 °C, but it volatilizes from the surface after calcination at 750 °C.

The present study is devoted to the development of perspective cathode (LiNiO2) and anode (lithiated SnO2) of solid-state lithium-ion batteries with the use of atomic layer deposition. The program of synthesis included a different number (ratio, 1/1–1/3) of lithium and metal oxide (Ni, Sn) deposition cycles in one supercycle. Lithium hexamethyldisilazide (LiHMDS), bis(cyclopentadienyl)nickel (II) (NiCp2) and tetraethyl tin (TET) were used as metal-containing reagents while oxygen remote plasma was used as a counter reagent. The deposition was conducted at 300 °C on the silicon surface and stainless-steel substrates. The obtained films were annealed at 400–700 °C for 10 min. Spectral ellipsometry, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XRR), X-ray diffraction (XRD) were used to characterize samples. The presence of silicon and nitrogen atoms was found in films which were not observed during deposition of lithium oxide and nickel oxide structures at the same synthesis conditions. The electrochemical behavior of synthesized Li-Ni-O and Li-Sn-O electrodes were studied.

The fabrication of nanocarbons possessing ultrathin graphitic structure and ultrahigh nitrogen doping simultaneously remains challenging so far. Herein, we develop a novel and versatile strategy to prepare ultrahigh nitrogen-doped hierarchical porous carbon with ultrathin graphitic framework (NHPCs), through the Schiff-base reaction of melamine and terephthalaldehyde in the presence of lithium oxide, as high-performance anodes for rechargeable lithium ion batteries. During one-pot solid-phase interface reaction, Li2O was used to absorb the in-situ generating H2O enhancing the formation of Schiff-based networks and LiOH was in-situ obtained, which can be used as active agent to increase the BET surface areas of final carbons. The obtained NHPCs present 3D hierarchical honeycomb-like morphology, ultrahigh nitrogen content up to 12.2 wt%, large specific surface area of 1260 m2 g−1. These unique structural properties allowed for fast ion diffusion and rapid electron transport, and offered enriched active sites for lithium storage. NHPCs presented a high reversible capacity of 880 mAh g−1 at 100 mA g−1 even after 100 cycles, and exceptional rate capability with 301 mAh g−1 at 3000 mA g−1, outperforming most reported nano‑carbons. Therefore, this strategy will open a new way to prepare heteroatom-doped porous carbons with a controllable hierarchical structure, for high-performance energy storage.

This study investigated the formation of a layered rock salt superstructure series for the oxides Li2(Mn1-xTix)O3 (0.0 ≤ x ≤ 1.0) and the effects of the progressive substitution of Ti4+ (d0) for Mn4+ (d3) on the structural and optical properties. The members where 0.0

The nano forms of the metals molybdenum oxide (MoO3), nickel oxide (NiO) and lithium oxide (Li2O) are finding wide application in advanced technologies including batteries and fuel cells. We evaluated soil responses to nanoMoO3, nanoNiO, and nanoLi2O as some environmental release of the materials, either directly or following the land application of biosolids, is expected. Using Drummer soil (Fine-silty, mixed, superactive, mesic Typic Endoaquolls), we evaluated the impacts of the three nanometals on soil gas (N2O, CH4, and CO2) emissions, enzyme activities (β-glucosidase and urease), and microbial community structure (bacterial, archaeal, and eukaryal) in a 60 day microcosms incubation. Soil treated with nanoLi2O at 474 μg Li/g soil, released 3.45 times more CO2 with respect to the control. Additionally, β-glucosidase activity was decreased while urease activity increased following nanoLi2O treatment. While no clear patterns were observed for gas emissions in soils exposed to nanoMoO3 and nanoNiO, we observed a temporary suppression of β-glucosidase activity in soil treated with either metal. All three domains of microbial community were affected by increasing metal concentrations. This is the first evaluation of soil responses to nanoMoO3, nanoNiO, or nanoLi2O.

Lithium titanate has been used as anode materials for litium batteries. Lithium titanate with stoichiometric formula (Li4Ti5O12) was prepared by the solid state method followed by sintering of the material. Lithium oxide (Li2O) and Titanium Oxide (TiO2) were taken as a base material to prepare the sample. The anode materials should have better ionic mobility. To enhance the ionic mobility of Lithium Titanate, Zr+4 is incorporated in the titanum site of Lithium Titanate. Incorporated Zr+4 with stoichiometries formula Li4Ti5-xAxO12, with x = 0.1, 0.2 and 0.3 weight percent respectively was prepared. Differential thermal analyses (DTA) of the prepared green sample had shown that the reaction completes at around 500°C. Thus, calcinations of the sample was done at temperatures greater than 500°C for an hour to get the proper phase of Lithium Titanate. X-ray diffraction (XRD) of the pure sample was carried out. Monoclinic phase was found in the material . Crystallite size was found in nm. Pellets were sintered at varying temperature rang e.g. 900°C, 950°C, 1000°C, 1050°C and 1100°C with soaking time of one hour. The measurement of mobility of charge carrier was measured using impedance analyser. The electrical properties of the sample were correlated with microstructure. Scanning Electron Microscopy (SEM) of the sintered sample shown the clear grain and grain boundaries with grains are in μm size. Frequency dependent resistance of Li4Ti5-xZrxO12, where x= 0.1, 0.2 & 0.3 weight percent has been studied.

In this study, nanoflaky maghemite (γ-Fe2O3) was successfully prepared by heating of synthesized lepidocrocite (γ-FeO(OH)). Once maghemite obtained, the electrochemical performance of nanoflaky maghemite, as an anode for Li-ion batteries, was investigated. Synthesis of lepidocrocite was optimized by adjusting the heating time and ratio of ethylene glycol (EG) to water in solution. The results revealed that with equal ratio of EG to water, the obtained phase was crystalline lepidocrocite whereas in other ratios lepidocrocite was not the only emerged phase. Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) results revealed that increasing heating time has no effect on morphology. This increment only led to the slight crystallite growth and agglomeration of precipitation. The optimized lepidocrocite were heated at 230 °C for 2 h to form maghemite, which was confirmed by using XRD. FESEM, high-resolution transmission electron microscopy, and nitrogen adsorption-desorption results disclosed that the particles have flaky morphology with thickness of less than 10 nm and surface area of 105 m2 g−1. Cyclic voltammetry results of anode body (prepared using nanoflaky maghemite) demonstrated reversible formation pathway of iron and lithium oxide through discharging and charging. Moreover, galvanostatic charge–discharge cycling showed a reversible capacity of about 480 mAh g−1 after 50 cycles at current density of 500 mA g−1. Good cyclability, and capacity retention of the anode is due to the nananometric size and flaky shape of the maghemite particles. These particles’ shape made it easier for them to expand and contract in thickness direction with minimized destructions imposed.

Trivalent europium doped aluminium phosphate glasses with different alkali oxides (Li2O, Na2O and K2O) have been prepared by melt quenching technique at 1200 °C. Photoluminescence properties of the obtained glasses have been studied and characterized. Also, Absorption and radiative properties of glasses are evaluated using the Judd–Ofelt (JO) theory. The emission spectra of all glasses remain the characteristic emission peak of Eu3+ with a dominant peak at 612 nm, corresponding to the 5D0 → 7F2 transition by monitoring an excitation wavelength at 393 nm. In the present glass system it was found that lithium oxide has higher intensity of emission spectra than sodium oxide and potassium oxide. The JO intensity parameters (Ω2, Ω4, Ω6) and subsequent radiative properties for the 5D0 → 7FJ (J = 1,2,3,4) transitions are determined. These glasses have potential candidate in the development as red laser source applications.

The reaction of lithium hydride (LiH) powder with pure water vapor (H2O and D2O) was studied by thermogravimetry and in situ infrared spectroscopy at 298 K over a large pressure range. The mean particle size of LiH is around 27 μm. At very low pressure, the hydrolysis starts with the formation of lithium oxide (Li2O). Then, both Li2O and lithium hydroxide (LiOH) are formed on increasing pressure, thus, creating a Li2O/LiOH bilayer. The reaction takes place through the consumption of LiH and the formation of Li2O at the LiH/Li2O interface and through the consumption of Li2O and the formation of LiOH at the Li2O/LiOH interface. Above 10 hPa, only the monohydrate LiOH·H2O is formed. This hydration reaction of LiOH into LiOH·H2O occurs at a lower pressure (8 hPa) after the first hydration-dehydration cycle. The hydrolysis mechanism proposed in this paper suggests that the diffusion of ionic species across the intermediate Li2O layer is the rate limiting step of the reaction.

A parametric study of the electrolytic reduction of uranium dioxide in molten lithium chloride – lithium oxide using carbon anodes was conducted to determine the operational parameter values necessary for high yields. Operational parameters evaluated in this study include anode and cathode current densities, anodic polarization, UO2 batch size, and method of electrochemical control. Seven oxide reduction experiments were conducted with between 25 g and 100 g UO2. The current density on the cathode was the critical parameter, which indicates the reduction process is kinetically controlled by cathodic reactions. High cell currents were achieved without the application of high anodic potentials by using a large anode surface area. This approach facilitates efficient reduction at high throughput without production of chlorine or other corrosive gasses.

We performed DFT calculations to investigate the role of solvent of the non-aqueous electrolytes for the oxygen reduction reaction (ORR) kinetics in Li-air batteries. The calculated results on structural, thermodynamic and vibrational properties revealed that dimethyl sulfoxide (DMSO) is the most stable solvent among DME, DMSO, and MeCN of non-aqueous electrolytes. The LiCF3SO3/DMSO electrolyte was primarily assumed to be the most favorable for ORR kinetics from the IR analysis. We calculated thermodynamic properties of the ORR reactions held during the formation of superoxide (O2−) ion and the sole discharge products lithium peroxide (Li2O2), and lithium oxide (Li2O) to study the ORR kinetics of the stable salt LiCF3SO3 with three solvents namely dimethoxyethane (DME), dimethyl sulfoxide (DMSO), and acetonitrile (MeCN). The thermodynamic properties of the ORR reaction signified the best role of LiCF3SO3/DMSO electrolyte compared to LiCF3SO3/DME and LiCF3SO3/MeCN both in the gas and solution (water) phases.

Silicon suboxide (SiOx) is a promising anode material for lithium ion batteries (LIBs), due to its high specific capacity, small volume variation and superior cycle performance. Herein, we demonstrated the determining roles of oxygen contents on the behavior of SiOx upon lithium by means of thin-film type electrodes. The SiOx thin-film anodes with different oxygen contents were prepared by sputtering with Cu foil as substrates. XRD and Raman investigations reveal that these SiOx films are amorphous. As anodes, it is found that increasing oxygen contents in SiOx endows an enhanced cycle stability, but does harm to their initial Coulombic efficiency and capacity. Among all the a-SiOx film anodes (x = 0.4, 0.7, 1.1 and 1.5), the SiO0.7 electrode with a thickness of 450 nm exhibits excellent cycle performance and rate capability, with a high initial discharge capacity of 463 μAh cm−2 μm−1 at the current density of 64 μA cm−2 and a high capacity retention of 90% after 300 cycles. This superior performance is ascribed to that the in-situ formed lithium oxide/silicates compounds during discharge effectively alleviates the large volume change of Si components, but also suppresses the electron leakage from the surface of active particles, shutting down the further decomposition of electrolytes and then the formation of thick solid interphase layer. These results will provide inspirations for designing high-performance Si based anodes for lithium ion batteries.

Sm3+ doped lead alumino-borate glasses containing ZnO, Li2O and BaO were synthesized and characterized for their structural and spectroscopic properties using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), optical absorption and luminescence measurements. The FTIR spectra, optical band gap and the values of density indicate formation of more BO4 units and a compact structure for the glass containing ZnO. Using optical absorption spectra, three phenomenological Judd-Ofelt parameters Ωλ (λ = 2, 4, 6) have been evaluated to determine the local structure and bonding in the vicinity of Sm3+ ions; the parameters are found to follow the trend Ω4> Ω6> Ω2. The parameter Ω2, which indicates the covalency of Sm O bond is found to be maximum for the glass containing zinc oxide followed by glasses with barium oxide and lithium oxide, in the decreasing order. . This result points towards a higher asymmetry and a less centro-symmetric coordination environment around the Sm3+ ions site for glass containing ZnO. The positive values of bonding parameter δ indicate a covalent nature of the Sm O bond for the glasses under study. The photoluminescence spectra recorded under an excitation of 402 nm exhibited four emission bands centered at about 562 nm, 597 nm, 642 nm and 706 nm corresponding to the transitions 4G5/2 → 6H5/2, 6H7/2, 6H9/2 and 6H11/2, respectively. The intensity of potential emission bands and radiative parameters such as branching ratio (βR) and stimulated emission cross-section ( σ ) are found to be higher for the glass containing zinc oxide. However, all other prepared glasses are also found to be efficient lasing materials showing suitability for the development of photonic materials emitting radiations in the reddish-orange range. The values of Figure of Merit (FOM) point towards a possible use of the prepared glasses as optical amplifier devices.

Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li2O films, measurements were made as a function of surface temperature (90–520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li2O films retained H in similar amounts as pure Li. Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.

Compounds of lithium oxide, hydroxide and carbonate, mixed with silver, were prepared for use as a cathode in caesium-sputter ion source. The intention was to determine the procedure which would produce the highest intensity negative lithium beams over extended period and with maximum stability. The chemical composition and properties of the samples were analysed using mass-spectrometry, optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analyses (EDX) and Raman spectroscopy. These analyses showed that the chemical transformations with components resulted from pressing, storage and bake out were qualitatively in agreement with expectations. Intensive negative lithium ion beams >1 μA were delivered using cathodes fabricated from materials with multicomponent chemical composition when the following conditions were met: (i) use of components with moderate enthalpy of formation; (ii) low moisture content at final stage of cathode production and (iii) small concentration of water molecules in hydrate phase in the cathode mixture.

The physical, optical, and gamma ray shielding behavior of the four Bi2O3-Li2O-P2O5 glasses with varying Li2O and Bi2O3 compositions have been explored. The glass density increases from 2.44 to 3.85 g cm-3 with bismuth oxide content. The molar volume follows the same trend as density and the overall molar volume of these glasses increases, which in turn directly affects the oxygen packing density (OPD). Optical band gap energies decrease after lithium oxide is replaced with bismuth oxide. The values of M lie between 0.3485 and 0.3209 indicates that glasses under investigation are non-metallic. Radiation shielding evaluation using EpiXS software and Phy-X/PSD program shows comparable mass attenuation coefficients (MACs) but with relatively higher percent differences at energies near the K-edge energies of O (0.538 keV) and Bi (90.5 keV). The MACs of the glasses rise when Li2O oxide is replaced with Bi2O3 oxide. The half-value layer (HVL) results showed the difference in the radiation shielding capabilities of the four glasses is more apparent at high energies. An increase in MAC and a decrease in HVL imply that adding Bi2O3 to the glass improves its radiation attenuation properties.

We propose a novel electrolyte additive, 5-acetylthiophene-2-carbonitrile (ATCN) with three functional groups (thiophene, nitrile and carbonyl), to in situ construct a stable cathode interface film that can significantly improve the cycling stability of LiCoO2 cathode under high-voltage. Adding 0.2% of ATCN into a base electrolyte, the capacity retention of LiCoO2/Li cell under 4.5 V is enhanced from 53% to 91% after 200 cycles at 1 C, and the cycle number of commercial LiCoO2/graphite pouch cell (34 Ah) with 10% capacity loss at 0.5 C under a cut-off voltage of 4.45 V is increased from 550 to 800. Experimental characterizations and theoretical calculations reveal that ATCN is preferentially oxidized on LiCoO2 cathode and utilizes its decomposition intermediates to convert the detrimental components, the hydrogen fluoride and water present in the electrolyte, and the lithium oxide and carbonate resulting from the electrolyte decomposition, into a unique film texture comprised of underneath compacted lithium salts and outer thiophene polymers. The as-constructed film significantly improves the cathode/electrolyte interface stability and the cycling stability of the cell. Such an effective strategy to address the interface instability has never been reported before and paves a new path to improve the energy density of commercial lithium-ion batteries via enhancing cut-off charge voltage.

We identify that reversible formation/decomposition of lithium oxide, pulverization of Fe3O4 nanoparticles, and electrolyte reactions, are contributors to the enhanced capacity observed in the Fe3O4 electrode upon long cycling. Introducing three-dimensional graphene foam to form a composite with Fe3O4 nanoparticles largely increases the capacity (~ 1220 mA h g−1 vs. ~ 690 mA h g−1) and promotes the cycling induced capacity enhancement (an earlier capacity rise and a faster rising rate) of the Fe3O4 electrode. Together with Fe3O4 nanoparticles, the presence of graphene effectively promotes the electrolyte reactions and reversible formation/decomposition of lithium oxide. At the same time, activation of GF also occurs in the presence of Fe3O4 nanoparticles, further increases the capacity of the nanocomposite.

The tritium breeding materials require small particle size to reduce the diffusion distance of generated tritium in the intercrystalline. In addition, the essential resource, especially enriched Li-6, has to be recovered from the used tritium breeding material. For the hands-on operation during the recovery process, the activation level of the used breeder is strictly limited in order to reduce the impurities of long-lived radioactive nuclides in the tritium breeding material. In this study, lithium oxide (Li2O) and titanium dioxide (TiO2) were used as starting materials in the synthesis of Li2TiO3 powder. The starting materials were mixed by wet ball-milling process. The mixed powders were synthesized by heat treatment. The average particle size of synthesized Li2TiO3 powder was approximately 150 nm. And, the long-lived radioactive nuclides, such as aluminum (Al) and cobalt (Co), were not accumulated in the synthesized Li2TiO3 powder during the synthesis process. The Li2TiO3 pebbles were fabricated by slurry droplet wetting method using the synthesized Li2TiO3 nano-powder. The particle size, crush load, and porosity of fabricated Li2TiO3 pebbles using the synthesized nano-powder were investigated.

Well understanding the role fluxing agents in the CaO-Al 2 O 3 -based slag system is essential to devise new mold fluxes for heat-resistant steel as well as for further improvement of data for viscosities and structure properties of the molten fluxes. The role of Li 2 O in CaO-Al 2 O 3 -Li 2 O-Ce 2 O 3 slag system was investigated through measuring viscosity combined with the FTIR spectra analysis. It was noted that Li 2 O show obvious effect of decreasing viscosity in the CaO-Al 2 O 3 -based slag system. The viscosity of the CaO-Al 2 O 3 -Li 2 O-Ce 2 O 3 slag melts decreased with increasing Li 2 O content. The relationship between the viscosity and the slag structure was discussed. Under the condition of increasing Li 2 O addition from 10 to 14 mass%, the relative ratio of [AlO 4 ]-tetrahedrons and [AlO 6 ]-octahedrons remain constant. The O 2– dissociated from Li 2 O just cut the network formed by [AlO 4 ]-tetrahedrons. The depolymerization of [AlO 4 ]-tetrahedrons from Q 4 units to Q 3 and Q 2 units was the main reason of the decrease of the viscosity. When the content of Li 2 O increased from 14 to 18 mass%, more and more O 2– dissociated from Li 2 O reacted with [AlO 4 ]-tetrahedrons to form [AlO 6 ]-octahedrons. The decrease of viscosity was mainly induced by the increase of free oxygen and the formation of [AlO 6 ]-octahedrons, which acts as a network modifier.

The structural and morphological changes occurred during the molten salt treatment of ilmenite (FeTiO3) are investigated by a variety of techniques including X-ray diffraction, scanning and transmission electron microscopy, as well as Raman and photoelectron spectroscopy. The phase evolution of ilmenite in molten LiCl under humid atmosphere leads to the facile formation of Li-containing phases such as Li0.8Ti2.2O4 and LiFeO2. Moreover, graphene nanosheets are successfully incorporated in the molten salt produced material through ball milling, and the Li-storage performance of the electrode made of the hybrid material is investigated. Unlike ilmenite, the hybrid structure exhibit an excellent electrochemical performance with a stable capacity of around 300 mAh g−1 after 500 successive discharge/charge cycles. This enhanced electrochemical performance is attributed to the presence of lithium oxide in the molten salt product that reduces the overall volume changes taking place during the lithiation/delithiation of the material, increasing the structural stability of the electrode. Furthermore, the presence of graphene nanosheets not only provides the electrical conductivity for the electrode, but also contributes to the structural stability of electrode by agglomerating the nanoparticles formed during cycling of the electrode. This article suggests a green and low-cost approach for the facile conversion of ilmenite into materials applicable for energy storage systems.

A reactional mechanism describing the hydrolysis of lithium hydride (LiH) under moist atmosphere is proposed and modeled. It involves the formation of lithium oxide (Li2O) at low vapor pressure and both lithium oxide and lithium hydroxide (LiOH) at higher vapor pressures, with diffusion of water in these layers. A numerical model based on this mechanism is implemented with COMSOL Multiphysics to simulate the hydrolysis of LiH particles in open system (constant water vapor pressure). Kinetic parameters such as rate constant of reactions and diffusion coefficient of water in Li2O and LiOH are first fitted against experimental data. The best agreements are obtained when the diffusion coefficient of water is 10 times higher in LiOH than in Li2O. The resulting model accurately predicts the hydrolysis rates experimentally measured for a wide range of water vapor pressures (0.3–17 Pa). The hydrolysis mechanisms are compatible with a Li2O production limited by water diffusion and a LiOH production governed by the kinetics. Finally, simulation suggest that the thickness of the Li2O layer does not depends much on the water vapor pressure whereas that of LiOH increases drastically at high water vapor pressures.

The paper presents results of investigations of optical absorption spatial changes in congruent bulk LiNbO3 crystals in 300–800 nm spectral region along Х, Y, Z directions caused by high-temperature (400–700 оС) annealing in Н2 and, subsequently, in air. As it is shown, the coloration/discoloration processes are anisotropic: a maximal depth of coloration is observed for Z direction and a minimal one – for X direction. The reversibility of optical properties with respect to the annealing atmosphere changes as well as results of investigations by SIMS and IR spectroscopy methods suggest that the oxygen loss/incorporation. processes play a major role in the coloration/discoloration. The additional absorption spectrum caused by reduction consists of three bands, whose nature is associated with different point defects: 350–410 nm – defects in anion sublattice, 500–520 nm – bipolarons; 700–750 nm – bound polarons. Individual contributions of the bands to the additional absorption spectra depend on the annealing temperature and on the distance from the crystal surface. During reduction lithium oxide is leaving the crystal which leads to the formation of Li2O-depleted structural phase LiNb3O8 in near-surface regions. Experimentally obtained distribution of depth-dependent additional absorption in reduced crystals was successfully approximated basing on the oxygen vacancies diffusion model and solution of differential equations set describing a quasichemical reaction of bipolarons formation due to the oxygen loss in LiNbO3 crystal. On the other hand, this model does not allow to describe accurately the depth-dependent discoloration after oxidizing annealing of previously reduced lithium niobate crystals.

Anode-supported micro-tubular solid oxide fuel cell (MT-SOFC) made from lithium (Li) doped cerium gadolinium oxide (CGO) electrolyte was prepared via phase inversion based co-extrusion/co-sintering technique. In this study, the co-sintering temperature of CGO electrolyte with anode layer was reduced by adding Li that acts as sintering additive. The prepared Li doped CGO (Li-CGO) were characterized by shrinkage analysis, atomic resolution analytical microscope (ARM) observation and X-ray photoelectron spectroscopy (XPS) spectra. Meanwhile, the developed half-cell of MT-SOFC which was co-sintered at 1350–1500 °C with interval of 50 °C were characterized by its mechanical strength, gas tightness and microstructural analysis. The electrochemical performances of the cells were tested in anode-supported MT-SOFCs with configuration of Ni-CGO anode, Li-CGO electrolyte and LSCF-CGO cathode using humidified hydrogen as fuel and oxygen air as oxidant. MT-SOFCs fabricated with Li-CGO electrolyte were found to exhibit maximum power density of 60 Wm − 2 at 500 °C compared to 200 Wm − 2 for cells with unmodified CGO electrolyte. The poor performance of cell with Li-CGO electrolyte is probably due to the combined effects of (i) moderately dense electrolyte layer and (ii) appearance of electronic conductivity in Li-CGO electrolyte. Nevertheless, lowering the sintering temperature has shown good properties of the electrolyte materials, which allows the electrolyte materials and anode can be co-sintered together at lower temperature.

Liquid metal plasma facing components (LMPFC) have shown a potential to supplant solid plasma facing components materials in the high heat flux regions of magnetic confinement fusion reactors due to the reduction or elimination of concerns over melting, wall damage, and erosion. To design a workable LMPFC, one must understand how liquid metal interacts with solid underlying structures. Wetting is an important factor in such interaction, several designs of LMPFC require liquid metal to wet the underlying solid structures. The wetting of lithium compounds (lithium nitride, oxide, and carbonate) by 200 °C liquid lithium at various surface temperature from 230 to 330 °C was studied by means of contact angle measurements. Wetting temperatures, defined as the temperature above which the contact angle is less than 90°, were measured. The wetting temperature was 257 °C for nitride, 259 °C for oxide, and 323 °C for carbonate. Surface tensions of solid lithium compounds were calculated from the contact angle measurements.

The application of lithium to plasma-facing components (PFCs) has long been used as a technique for wall conditioning in magnetic confinement devices to improve plasma performance. Determining the characteristics of PFCs at the time of exposure to the plasma, however, is difficult because they can only be analyzed after venting the vacuum vessel and removing them at the end of an operational period. The Materials Analysis and Particle Probe (MAPP) addresses this problem by enabling PFC samples to be exposed to plasmas, and then withdrawn into an analysis chamber without breaking vacuum. The MAPP system was used to introduce samples that matched the metallic PFCs of the Lithium Tokamak Experiment (LTX). Lithium that was subsequently evaporated onto the walls also covered the MAPP samples, which were then subject to LTX discharges. In vacuo extraction and analysis of the samples indicated that lithium oxide formed on the PFCs, but improved plasma performance persisted in LTX. The reduced recycling this suggests is consistent with separate surface science experiments that demonstrated deuterium retention in the presence of lithium oxide films. Since oxygen decreases the thermal stability of the deuterium in the film, the release of deuterium was observed below the lithium deuteride dissociation temperature. This may explain what occurred when lithium was applied to the surface of the NSTX Liquid Lithium Divertor (LLD). The LLD had segments with individual heaters, and the deuterium-alpha emission was clearly lower in the cooler regions. The plan for NSTX-U is to replace the graphite tiles with high-Z PFCs, and apply lithium to their surfaces with lithium evaporation. Experiments with lithium coatings on such PFCs suggest that deuterium could still be retained if lithium compounds form, but limiting their surface temperatures may be necessary.

Li 2 ZnTi 3 O 8 @C anode material has been synthesized by a facile solid-state reaction method, in which C 6 H 5 Li 3 O 7 ·4H 2 O is used as the lithium source, as well as the single-source carbon. With the formation of carbon-wrapped lithium oxide by the thermolysis of single-component precursor C 6 H 5 Li 3 O 7 ·4H 2 O, Li 2 ZnTi 3 O 8 particles are produced in a limited area, which could effectively hinder their growth/agglomeration. Moreover, the carbon layer coating on the outer surface of Li 2 ZnTi 3 O 8 is also beneficial to the transfer of both Li + and electrons, then an enhanced electrochemical performance is expected to achieve. From the electrochemical test results, a reversible capacity of 227.4 mAh g −1 could be delivered by Li 2 ZnTi 3 O 8 @C after 100 cycles at the current rate of 2 C.

Hematite (Fe2O3) nanoparticles and reduced graphene oxide (rGO) were supersonically sprayed onto copper current collectors to create high-performance, binder-free lithium ion battery (LIB) electrodes. Supersonic spray deposition is rapid, low-cost, and suitable for large-scale production. Supersonic impact of rGO sheets and Fe2O3 nanoparticles on the substrate produces compacted nanocomposite films with short diffusion lengths for Li+ ions. This structure produces high reversible capacity and markedly improved capacity retention over many cycles. Decomposition of lithium oxide generated during cycling activates the solid electrolyte interface layer, contributing to high capacity retention. The optimal composition ratio of rGO to Fe2O3 was 9.1 wt.%, which produced a reversible capacity of 1242 mAh g−1 after N = 305 cycles at a current density of 1000 mA g−1 (1C).

Lithium oxide excess and powder bed method are conventionally used for synthesis of lithium-conducting solid electrolytes with cubic garnet structure. In this work Li 6.75 La 3 Zr 1.75 Nb 0.25 O 12 garnet was sintered at 1200 °C on alumina and zirconia supports with controlled amount of lithium oxide excess. It was found that the powder bed method did not prevent garnet pellets from alumina contamination. The quantity of aluminum penetrated into samples correlated with the amount of lithium oxide excess added and varied from 0.2 to 0.5 wt%, as indicated by ICP AES. In contrast to alumina, zirconia did not affect chemical composition of the pellets. Taking this into account to avoid any alumina contamination a modified powder bed method was developed. However, non-contaminated samples showed lower density after sintering when compared to contaminated ones. Lithium oxide excess in the samples is likely to react with the alumina with formation of eutectic that melts at 1200 °C. The liquid eutectic phase acts as a sintering aid and promotes densification up to relative densities of 96%. Electrical properties of the pellets were measured by EIS technique. Bulk conductivity of the dense pellets was 5 × 10 − 4 S/cm at 25 °C with the activation energy of 0.3 eV and depends on density. Due to grain boundary resistance dc-conductivity of pellets was lower than 10 − 8 S/cm at 25 °C with the activation energy of 0.8 eV. Possible reasons of high grain boundary resistance are discussed.

In order to exchange the components which received irradiation damage during the operation at the International Fusion Materials Irradiation Facility, the adhered lithium, which is partially converted to lithium compounds such as lithium oxide and lithium hydroxide, should be removed from the components. In this study, the dissolution experiments of lithium compounds (lithium nitride, lithium hydroxide, and lithium oxide) were performed in a candidate solvent, allowing the clarification of time and temperature dependence. Based on the results, a cleaning procedure for adhered lithium on the inner surface of the components was proposed., 国際核融合材料照射試験施設(IFMIF)の中性子源として使用されるリチウムは、大気中の酸素や窒素と容易に化学反応を生じる。IFMIFにおいて使用機器の交換の場合には、その機器に付着したリチウムは、酸化リチウムや水酸化リチウムのようなリチウムに変化することから、これらを交換する機器から安全に除去することが要求される。本研究では、候補洗浄剤であるエタノール中における各種のリチウム化合物(窒化物、水酸化物および酸化物)の溶解挙動について、温度および時間をパラメータに調べた。

An integral experiment on molybdenum is performed with a DT neutron source at JAEA/FNS. A Mo assembly is covered with lithium oxide blocks in order to reduce background neutrons inside the assembly. Several reaction rates and fission rates are measured along the central axis inside the assembly and compared with calculated ones with the Monte Carlo transport code MCNP5-1.40 and recent nuclear data libraries of ENDF/B-VII.1, JENDL-4.0, and JEFF-3.2. The calculated results generally show underestimation. From our detailed analysis, it is concluded that the (n,2n) cross section data of all the Mo stable isotopes in JEFF-3.2 are more suitable than those in JENDL-4.0 and the (n,γ) cross section data of 92Mo, 94Mo, 95Mo, 96Mo, 97Mo, and 100Mo in JENDL-4.0 are overestimated.

Instrumentation to provide process monitoring (PM) and safeguards for the oxide reduction (OR) step in the electrochemical processing of used oxide nuclear fuel is necessary to ensure equipment is operated as declared. Cyclic voltammetry (CV) has been proposed for real-time monitoring of the operation of an OR process for safeguards purposes. In this study, 316L stainless steel (SS), tantalum (Ta), molybdenum (Mo), tungsten (W), platinum (Pt), and iridium (Ir) were evaluated as potential working electrode (WE) materials based on their chemical inertness, corrosion resistance, and sensitivity in detecting lithium oxide (Li2O) and other chloride salts in the OR electrolyte. Of the electrodes evaluated, 316L SS, Ir, and Pt all performed reasonably well in the lithium chloride-lithium oxide (LiCl-Li2O) electrolyte. SS was operated in the cathodic potential, had reasonable corrosion resistance, and is relatively inexpensive. Ir could be operated in both the cathodic and anodic potentials and was the most corrosion-resistant of the materials evaluated. Pt is limited to the anodic potential range, had reasonable corrosion resistance, and was the most sensitive to Li2O concentrations in the salt. In the development of a stand-alone safeguards instrumentation, our recommendation is a CV probe fitted with both Ir and Pt WEs. The results of this study may also be helpful for anode material selection in other electrometallurgy industries, such as molten salt electrolysis.

Effect of lithium oxide substitution on the structure, in-vitro chemical dissolution and mechanical properties of melt derived 45S5 based glass-ceramics in 46.1SiO2 (24.4-x)Na2O 26.9CaO 2.6P2O5 x Li2O (x = 0, 2, 4, 6, and 10 mole %) system was studied. Raman analysis had shown the presence of Q2 silica tetrahedra and crystalline phosphorus in the glass-ceramics samples. Higher mechanical properties of lithia containing glass and glass-ceramics were noticed due to compact glass structure in presence of small sized Li+ ions. Hexagonal shaped combeite (Na2O.2CaO.3SiO2) was the only crystalline phase. Fourier transform infrared spectroscopy (FTIR) and Raman spectra confirmed formation of carbonated hydroxyapatite (HCA) on the glass-ceramics surface in SBF solution. Scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) corroborated cotton ball like morphology as carbonated hydroxyapatitel ayer on lithium containing glass-ceramics sample surface.

The ionic conductivity in lithium borate glasses RLi2O-B2O3 is believed to be related to the number of loose lithium ions, calculated using the topological constraint theory, increasing significantly when 0 ≤ R ≤ 0.5 and reaching a plateau when 0.5 ≤ R ≤ 1.0, and increasing once again when R ≥ 1.0. To test this new proposed approach, high content lithium oxide glasses were prepared (up to R = 1.85) without any signs of heterogeneity by using a fast quenching technique. Results show that instead of being related to the number of loose lithium ions, the ionic conductivity is mostly likely related to the different boron species which act as lithium sites, given that the number of non-bridging oxygens increases proportionally to the lithium to boron ratio when R ≥ 0.5, the region where the plateau in electrical properties is observed.

For improved understanding of the behavior of Li plasma facing components (PFCs) in the presence of oxygen impurities, we report on the thermal stability of ultrathin (up to 1.0 nm) LiOx films on a titanium-zirconium-molybdenum (TZM) alloy substrate over the temperature range of 310–1400 K. LiOx films were prepared by either post-oxidation of Li films or Li films deposited on an oxygen-precovered TZM surface. Thermal stability of these films was studied using a combination of temperature programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), and low-energy ion scattering (LEIS). For post-oxidized Li films, TPD showed that no Li desorption occurred until temperatures above 620 K, and then Li desorbed from the surface via at least three desorption peaks. The O 1s XPS spectra on the post-oxidized films at 310 K indicate the formation of lithium oxide (Li2O) and peroxide/hydroxide (Li2O2/LiOH). The peroxide/hydroxide converts to oxide after heating to 680 K with no desorption of Li or O2, and then this film decomposes to liberate Li into the gas phase while leaving oxygen at the TZM surface. Heating the LiOx films to 1070 K led to a solid-state reaction with surface Mo atoms of the substrate to form a condensed binary lithium molybdenum oxide (LixMoOy) phase, which upon further heating decomposed to liberate gas phase binary lithium molybdenum oxide species. Li deposition on an oxygen-precovered TZM surface formed a complex, highly stable, oxygen rich, Li-O-Mo interfacial oxide. Li desorption from multilayer Li films on oxygen-precovered TZM surfaces occurred in a metallic Li multilayer peak and three other oxide-derived peaks. These results support the improved thermal stability of oxidized lithium as compared to metallic Li and have implications for Mo impurity transport into the plasma at high temperatures.

Improving electrochemical performance of cathode materials for lithium-ion batteries requires comprehensive understanding of their structural properties which could facilitate or impede the diffusion of lithium during charge-discharge. In order to optimize the structure and improve the electrochemical performance of layered cathode material, the detailed structural evolution as a function of heat treatment temperature in LiNi0.8Co0.1Mn0.1O2 was investigated by in-situ and ex-situ neutron powder diffraction methods. We show that both cycling stability and rate performance of LiNi0.8Co0.1Mn0.1O2 can be improved by performing heat treatment at 400 °C, which is attributed to the optimization of surface structure and the enlargement of c/a ratio. Heat treatment of LiNi0.8Co0.1Mn0.1O2 at higher temperature induces a layered-to-rock-salt structure phase transition accompanied with the precipitation of lithium oxide. A 3D phase diagram, which correlates the high temperature phases and room temperature phases, is constructed. The presentation of comprehensive phase diagrams up to 1000 °C could provide the basis for further research on not only synthesis strategy but also thermal stability in Ni-rich layered cathode materials.

Zinc bismuth borate glasses modified by lithium oxide with composition (25-x) Bi2O3–60B2O3–15ZnO-xLi2O, where, x = 5, 10, 15, 20 and 25 mol% have been synthesized using standard melt quenching technique. Amorphous nature of the glass samples has been ascertained by appearance of broad hump in X-ray diffraction patterns. FTIR and Raman studies advocated that glass structure is mainly built of [BO4], [BO3] and [ZnO4] structural units, however, Bi2O3 exists primarily as [BiO6] octahedral units. The glass transition temperature (Tg) shows a non-linear variation with increase in Li2O content. Trend in the values of ‘Tg’ is in accordance with change in structure of glass matrix (i.e. fraction of [BO4] units (N4) on addition of Li2O). The values of density (ρ), molar volume (Vm) and crystalline volume (Vc) are found to decrease with increase in Li2O content. The percentage value of transmittance is found to increase with increase in Li2O content. Optical band gap energy ‘Eg’ values has been determined from fitting of experimental data with Tauc’s relation and Hydrogenic excitonic model (HEM) and are found in the range of 2.432–3.211 eV. The HEM model shows good agreement with experimentally observed data, indicates the exciton formation in studied glass system. The values of Urbach energy (ΔE) have been estimated by fitting of experimental data with a new empirical relation and its values are found in the range of 0.194 eV–0.294 eV. The values of metallization criterion (M) were found in the range of 0.349–0.401, suggesting that the prepared glasses may be considered as potential candidate for non-linear optical applications.

Lithium oxide (Li2O) is activated in the presence of a layered composite cathode material (HEM) significantly increasing the energy density of lithium-ion batteries. The degree of activation depends on the current rate, electrolyte salt, and anode type. In full-cell tests, the Li2O was used as a lithium source to counter the first-cycle irreversibility of high-capacity composite alloy anodes. When Li2O is mixed with HEM to serve as a cathode, the electrochemical performance was improved in a full cell having an SiO-SnCoC composite as an anode. The mechanism behind the Li2O activation could also explain the first charge plateau and the abnormal high capacity associated with these high energy cathode materials.

We have sought the structural origin of the recently reported electrical conductivity of lithium copper phosphate glass system (50-x) Li 2 O-xCu 2 O-50 P 2 O 5 , as lithium oxide is gradually replaced by Cu 2 O. The structure of these glasses was determined by X-ray photoelectron spectroscopy, Fourier Transform Infrared Spectroscopy and Raman spectroscopy. The results show the presence of both mobile Cu + and relatively immobile Cu 2+ ions. The relative fraction of Cu 2+ [Cu 2+ / Cu tot ] and non-bridging oxygen increases with x; the latter indicating a tendency towards depolymerization of the network. On the other hand, there is enhanced crosslinking within the network as P O ⋯ Li bonds are replaced by relatively covalent P O ⋯ Cu bonds. This leads to a more cross-linked structure and a progressive reduction of the optimum sites for the jumping of both Li + and Cu + , in agreement with the observed increase of the energy barrier for ion transport as Li 2 O is replaced by Cu 2 O.

Lithium ion conducting glasses in xLi2O–(1-x)(0.75B2O3–0.25SiO2) system have been obtained and studied in the x range from 50 to 67.5 mol%. The influence of the lithium oxide content on the glass transition temperature (Tg), crystallisation temperature (Tc), density, structure and ionic conductivity has been investigated. We establish that the anomalous behavior of the properties is observed at the point with Li2O concentration of 62.5 mol%. The value of maximal conductivity at room temperature is 3.6 ⋅ 10− 6 S/cm for the glass containing 65.0 mol% of lithium oxide.

Sputter deposition of the thin film memristor material, lithium niobite (LiNbO2) is performed by co-deposition from a lithium oxide (Li2O) and a niobium target. Crystalline films that are textured about the (101) orientation are produced under room temperature conditions. This material displays memristive hysteresis and exhibits XPS spectra similar to MBE and bulk grown LiNbO2. Various deposition parameters were investigated resulting in variations in the deposition rate, film crystallinity, oxygen to niobium ratio, and mean niobium oxidation state. The results of this study allow for the routine production of large area LiNbO2 films at low substrate temperature useful in hybrid-integration of memristor, optical, and energy storage applications.

Herein, we describe a new simple method to improve the irreversible performance of a SiO anode during the initial cycle. The solid state-reacted SiO material was synthesized from bare SiO and lithium powders (three samples with weight ratios of 7:1, 8:1, and 9:1 were prepared) using a heat treatment process at 600 °C. Irreversible phases such as lithium silicates (Li4SiO4 and Li2SiO3) and Li2O were formed upon the solid state reaction with SiO. Electrochemical tests using half-cells were performed to confirm the effects of the solid state-reacted SiO material. The initial Coulombic efficiencies of the three samples were 82.12% (7:1), 79.81% (8:1), and 78.95% (9:1), which were far higher than that of a bare SiO cell (58.52%). Furthermore, the electrochemical performance of a full cell using a 7:1 wt% SiO anode and a lithium cobalt oxide cathode was evaluated. The full cell exhibited an initial Coulombic efficiency of 93.62% and a capacity retention of 74.70% after 15 cycles, which were also far higher than those of a bare SiO cell (66.4% and 55.72%, respectively). A comparison of the solid state-reacted and bare SiO electrodes demonstrated that the pre-formed irreversible phases prevented the consumption of lithium ions during the 1st cycle.

We recently proposed a new battery system based on the redox of lithium peroxide (Li 2 O 2 )/lithium oxide (Li 2 O) at the cathode (lithium-peroxide battery system). In this system, the use of Li 2 O with cobalt ions partially substituted for lithium ions (Co-doped Li 2 O) is key to its realization. In this study, to further improve the cell performance, we prepare various Co-doped Li 2 O samples by a mechanochemical process using different cobalt source materials (e.g., LiCoO 2 , Co 3 O 4 , and CoO) and comparatively investigate them. Amongst the investigated cathode materials, the Co-doped Li 2 O sample prepared using LiCoO 2 with a Co/(Co + Li) ratio of 0.09 exhibits the best performance. Monitoring of the pressure in the cell reveals that this Co-doped Li 2 O cathode can be charged to 270 mAh g −1 without O 2 evolution involving its decomposition. Charge and discharge at 270 mAh g −1 is repeated more than 50 times. In addition, the rate-capability tests reveals that the redox reaction between peroxide and oxide ions is fast and that the cathode can be discharged at a high current density of 1000 mA g −1 .

During the discharge of an aprotic Li/O 2 battery solid products assemble inside of the gas diffusion electrodes (GDE). The distribution of these in dependence of pore size of the GDE is investigated by X-ray Photoelectron Spectroscopy (XPS). Depth profiling of the electrolyte facing side of the cathode reveal that macroporous electrodes are able to store discharge products homogeneously in the pore structure. Mesoporous GDE, however, develop a concentration gradient with large amounts of discharge product at the electrode/electrolyte interface and low amount in the bulk of the electrode. The investigation of the cross-section of these GDE reveals that most of the discharge products form near the oxygen facing side of the GDE. Here, the chemical compositions differ strongly from those at the electrolyte facing side. The high oxygen concentration and the limited lithium supply lead to the formation of lithium carbonate, lithium oxide and lithium fluoride. Also a thin layer of discharge product blocking further oxygen supply into the GDE through macroporous cracks is formed at the gas/electrolyte interface.

Density functional theory calculations are performed to investigate the role of lithium salts regarding the oxygen reduction reaction (ORR) occurred in non-aqueous electrolyte in Li-air batteries. This study is useful to elucidate the influence of ion-conducting lithium salts on ORR kinetics. The Li + -O bonding, binding energy, Gibb's free energy, heat of formation energy, and IR spectra with increase in dimethyl sulfoxide (DMSO) solvent molecules in the primary solvation shell reveal that lithium trifluoromethanesulfonate (LiCF 3 SO 3 ) is the most stable in dimethyl sulfoxide (DMSO) as compared to lithium hexafluorophosphate (LiPF 6 ) and lithium bis(trifluoromethanesulfonimide (LiN(CF 3 SO 2 ) 2 ). Infrared spectroscopic (IR) data confirm the formation of lithium peroxide (Li 2 O 2 ), lithium oxide (Li 2 O), and lithium carbonate (Li 2 CO 3 ) as discharge products on the micro-electrode surface in non-aqueous electrolyte containing lithium salts. The infrared (IR) analysis reveals that the lithium trifluoromethanesulfonate/dimethyl sulfoxide (LiCF 3 SO 3 /DMSO) electrolyte is primarily assumed to be the most favorable for ORR kinetics. In order to study the kinetics of oxygen reduction reaction at the oxygen cathode of non-aqueous Li-air battery with three Li salts in dimethyl sulfoxide (DMSO), we calculate thermodynamic properties of the reactions held during the formation of lithium peroxide (Li 2 O 2 ) and lithium oxide (Li 2 O). The Gibb's energy and heat of formation of these reactions indicate that lithium trifluoromethanesulfonate/dimethyl sulfoxide (LiCF 3 SO 3 /DMSO) electrolyte plays a key role in oxygen reduction reaction mechanism compared to other two.

We present the electrical and the phonon vibrational properties of Li2O–2SiO2 (LS12) and Li2O–SiO2 (LS11) glasses to exploit for lithium ion transport in the merits of solid electrolyte. Electrical impedance measurements are carried out in the frequency 100 Hz–30 MHz and temperature range 30–150 °C. Based on the theory of the modified fractional Rayleigh equation, we predict the number densities of the lithium ions in the lithium silicate glasses. As an increase in lithium content, the covalent interaction between the Li-cation and its local sites of network increases the number of the non-bridging oxygen (NBO) sites by the depolymerization of the silicate glass network. We find the fact that the number of NBOs in the LS11 glass increases a factor of two larger than the number of NBOs in the LS12 glass. A low conductivity of lithium oxide glasses is reflection of a long stay of the lithium ions in the NBO atoms. The partial Li+ ions in the lithium silicate glasses participate on the ac conduction through the NBO sites.

Gold nanoparticles (NPs) exhibit strong surface plasmon resonance (SPR) in the visible spectral region. Lithium Zinc Calcium Fluoroborate glasses embedded with Au NPs were synthesized by conventional melt quench technique. The gold NPs embedded glasses exhibited dichroic nature. A small kink around 44.61∘ in the X-ray diffraction (XRD) pattern suggests the presence of Au (2 0 0) in the matrix. High resolution-transmission electron microscopic (HR-TEM) measurements further confirmed the existence of spherical and ellipsoidal Au NPs. Thermogravimetric analysis (TGA) reveals the role of network modifiers in the matrix as the glasses that contained higher concentration of lithium oxide exhibits lower Tg thereby resulting in creation of more non bridging oxides (NBO's). The Z-Scan studies were performed under non-resonant condition (800 nm) to analyze the application of these glasses for optical limiting devices.