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1
Hanquet, B., B. Tabyaoui, J. C. Caille, M. Farnier e R. Guilard. "Synthèse stéréosélective de (±) boschnialactone, (±) 7-épiteucriumlactone et (±) 7-épiisoiridomyrmécine. Étude de la stéréochimie par spectroscopie de résonance magnétique nucléaire". Canadian Journal of Chemistry 68, n. 4 (1 aprile 1990): 620–27. http://dx.doi.org/10.1139/v90-095.
Testo completoAbstract (sommario):
The stereoselective syntheses of (±) boschnialactone 1, (±) 7-epiteucriumlactone 2, and (±) 7-epiisoiridomyrmecine 3 are described. Their preparation involved Stetter's reaction followed by nucleophilic addition of lithium enolates of suitable esters. Silylated reagents are used in the lactonisation step and the observed yields are between 63 and 78%. The proposed structural analysis is not in accord with the results of a previous study. The nuclear magnetic resonance data are determined using ID and 2D proton and carbon NMR experiments. Keywords: stereoselective synthesis, boschnialactone, 7-epiteucriumlactone, 7-epiisoiridomyrmecine, 1H and 13C NMR.
2
Seo, Ambrose, Andrew Meyer, Sujan Shrestha, Ming Wang, Xingcheng Xiao e Yang-Tse Cheng. "Observation of the surface layer of lithium metal using in situ spectroscopy". Applied Physics Letters 120, n. 21 (23 maggio 2022): 211602. http://dx.doi.org/10.1063/5.0096546.
Testo completoAbstract (sommario):
We have investigated the surface of lithium metal using x-ray photoemission spectroscopy and optical spectroscopic ellipsometry. Even if we prepare the surface of lithium metal rigorously by chemical cleaning and mechanical polishing inside a glovebox, both spectroscopic investigations show the existence of a few tens of nanometer-thick surface layers, consisting of lithium oxides and lithium carbonates. When lithium metal is exposed to room air (∼50% moisture), in situ real-time monitoring of optical spectra indicates that the surface layer grows at a rate of approximately 24 nm/min, presumably driven by an interface-controlled process. Our results hint that surface-layer-free lithium metals are formidable to achieve by a simple cleaning/polishing method, suggesting that the initial interface between lithium metal electrodes and solid-state electrolytes in fabricated lithium metal batteries can differ from an ideal lithium/electrolyte contact.
3
Zhang, Li, Tao Qian, Xingyu Zhu, Zhongli Hu, Mengfan Wang, Liya Zhang, Tao Jiang, Jing-Hua Tian e Chenglin Yan. "In situ optical spectroscopy characterization for optimal design of lithium–sulfur batteries". Chemical Society Reviews 48, n. 22 (2019): 5432–53. http://dx.doi.org/10.1039/c9cs00381a.
Testo completoAbstract (sommario):
Recent advances in optimal design of lithium–sulfur batteries with the aid of in situ optical spectroscopic techniques, including Raman, infrared and ultraviolet-visible spectroscopies, are systematically summarized.
4
Meyer, Lydia, Collin Kinder e Jason Morgan Porter. "Chemometric and Machine Learning Analysis of Lithium Concentration and Solvation Behavior in Li-Ion Battery Electrolytes". ECS Meeting Abstracts MA2022-02, n. 6 (9 ottobre 2022): 618. http://dx.doi.org/10.1149/ma2022-026618mtgabs.
Testo completoAbstract (sommario):
The demand for batteries is rapidly growing across a range of technologies. The increasingly diverse use cases for batteries require various capabilities, particularly requirements for high energy densities, that are currently unmet by traditional Li-ion batteries. Electrolyte stability proves to be a bottleneck for battery advancement towards energy dense chemistries beyond Li-ion, including metal anodes. In situ spectroscopy tools, such as Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray spectroscopy, have provided insight into critical molecular-level interactions in batteries during cycling. These in situ tools have yielded continuous improvement of electrolyte properties. Spectroscopy datasets, however, contain many nuances that challenge meaningful human understanding. Artificial intelligence and chemometric tools can be coupled with in situ spectroscopy to find relevant interpretations of spectral datasets and elucidate complex molecular phenomena. In this research, an analysis was performed on FTIR spectroscopy data from an electrolyte composed of LiPF6 in ethylene carbonate (EC) and ethyl methyl carbonate (EMC) to discern solvation behavior using principal component analysis (PCA) and a convolutional neural network (CNN). PCA pinpointed exact band locations of solvation shifting behavior in the IR spectra and improved understanding of the relationship between lithium concentrations and peak changes. The CNN was trained with spectral datasets of electrolytes with known lithium concentrations and then could predict lithium concentrations from spectral datasets with extraordinarily high accuracy. Additionally, the CNN interpreted FTIR spectral datasets from a graphite half-cell with EC/EMC/LiPF6 electrolyte and accurately determined the lithium concentration in the bulk electrolyte. The CNN also observed lithium depletion events (up to 10% lithium depletion) in the graphite anode during fast-charging cycles of the galvanostatic intermittent titration technique. This research breaks new ground on using advanced computational tools for in situ spectroscopic analysis of battery electrolytes and demonstrates an improved understanding of complex molecular-level phenomena in electrolytes.
5
Cai Jiahua, 才家华, 张保龙 Zhang Baolong, 耿春艳 Geng Chunyan, 郝思博 Hao Sibo, 陈赛 Chen Sai e 吴晓君 Wu Xiaojun. "铌酸锂强场太赫兹非线性时域光谱系统". Chinese Journal of Lasers 50, n. 17 (2023): 1714012. http://dx.doi.org/10.3788/cjl230435.
Testo completo
6
Muhammad, F. H., A. F. M. Fadzil e Tan Winie. "FTIR and Electrical Studies of Hexanoyl Chitosan-Based Nanocomposite Polymer Electrolytes". Advanced Materials Research 1043 (ottobre 2014): 36–39. http://dx.doi.org/10.4028/www.scientific.net/amr.1043.36.
Testo completoAbstract (sommario):
Films of hexanoyl chitosan-based polymer electrolytes were prepared using solution casting technique. The interactions between hexanoyl chitosan-lithium perchlorate (LiClO4) and dimethyl carbonate (DMC)-lithium perchlorate (LiClO4) were investigated using Fourier transform infrared spectroscopy (FTIR). The FTIR results showed that there is a possible complexation between the electron donor of hexanoyl chitosan and DMC with lithium salt due to the shifting in the wavenumber and changes in the intensity of the infrared bands. The obtained spectroscopic data has been correlated with the conductivity performance of hexanoyl chitosan-based polymer electrolyte. The ionic conductivity was increased with addition of filler TiO2 and plasticizer DMC to the electrolyte system.
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Katime-Santrich, Orlando J., Bruno V. Castilho, Carlos A. O. Torres e Germano R. Quast. "Photometric and spectroscopic analysis of the stellar association AB Doradus". Proceedings of the International Astronomical Union 5, S265 (agosto 2009): 370–71. http://dx.doi.org/10.1017/s1743921310000979.
Testo completoAbstract (sommario):
AbstractWe present the stellar parameters and lithium abundance for 23 stars of the young stellar association AB Doradus, determined by photometry and spectroscopy. The photometric data was obtained at OPD/LNA and/or from the literature and the spectroscopic data was obtained at La silla/ESO and at OPD/LNA. The parameters were determined using photometric calibrations, line ratios, curves of growth and spectral synthesis. Our results confirm that the selected stars are probably association members, showing an uniform metallicity and lithium depletion consistent with 50 Myears
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Fritzke, Jana Beatrice, Sunita Dey, Christopher A. O'Keefe e Clare P. Grey. "NMR Spectroscopic Investigations of the Performance Limiting Mechanisms of Lithium-Sulfur Batteries". ECS Meeting Abstracts MA2023-02, n. 55 (22 dicembre 2023): 2692. http://dx.doi.org/10.1149/ma2023-02552692mtgabs.
Testo completoAbstract (sommario):
During the past decades, the development of alternative energy sources has become increasingly important as the growing consumption of non-regenerative fossil energy poses a threat to the environment. Hence, developing of next-generation batteries featuring high capacity, reduced costs and improved safety, such as in lithium-sulfur batteries, is of utmost importance. The benefits of lithium-sulfur batteries have led to widespread efforts to understand the fundamentals of the sulfur redox chemistry that drives their operation, as capacity fade has been observed in almost all Li-S batteries.[1] Therefore, the involved local structural changes that correlate with the (electro)chemical processes need to be unveiled during the operation of Li-S batteries, suitably by in situ and in operando methods. This presentation will demonstrate the development and application of one such (operando) technique: nuclear magnetic resonance (NMR) spectroscopy. NMR spectroscopic measurements allow the probing of the structural changes in a battery during electrochemical cycling. In particular, the application of a non-invasive experimental set-up, which can follow the reaction inside the battery in operando is highly desirable as it provides real-time structural information compared to ex situ analysis.[2] Lithium-sulfur batteries contain various NMR-active nuclear isotopes, like 7Li, 6Li and 33S, which allow the following of the chemical reactions during the charge-discharge process. This includes the transition between elemental sulfur and polysulfides on the cathode side, the formation of the solid-electrolyte interface (SEI) and the metal plating and stripping on the anode side. Herein, we use for the first time a combination of lithium and sulfur in operando NMR spectroscopy to reveal a fundamental understanding of the reaction pathway of lithium-sulfur batteries during the cycling process. Lithium NMR spectroscopy is a powerful technique to apply to batteries, as demonstrated by many previous investigations on different lithium battery systems, since it enables the detection of the chemical environments of lithium species during electrochemical cycling and parasitic reactions in the cell.[3] The great advantage of in operando 7Li NMR spectroscopy is that the 7Li signals of the lithium anode and the deposited metal differ due to the bulk magnetic susceptibility effects and the surface area, bringing the skin depth effect into play. Thus, this method enables a time-resolved and quantitative evaluation of the electrochemical metal deposition during electrochemical cycling. Therefore, it is possible to investigate a critical problem that reduces the cell performance – the formation of lithium dendrites. This lithium deposition is particularly problematic if it occurs uncontrolled and inhomogeneous and the exact mechanism of nucleation and propagation of dendrites is not yet fully understood.[4] The developed technique helps to understand this deposition to improve the safety during cycling. The interpretation of the electrolyte signal in the in operando 7Li spectra is much more difficult because of the overlapping signals. Therefore, in situ 33S and 6Li NMR spectroscopy supports the identification and quantification of (poly-)sulfides during the charge-discharge-process. 33S NMR experiments are rarely reported since 33S is a quadrupolar nucleus characterized by a low natural abundance and magnetogyric ratio, resulting in a very low receptivity. Nevertheless, the developed 33S NMR technique allows the detection of the formation Li2S under in operando conditions.[5] Additional in operando 6Li NMR experiments allow to follow the (poly-)sulfide formation as the spectra yield much sharper lines in asymmetric lithium environments in comparison to 7Li NMR experiments.[6] Thus, these techniques provide complementary results to the 7Li NMR spectroscopic studies and help to elucidate the sulfur redox mechanism in lithium-sulfur batteries. Our developed in situ NMR spectroscopic set-up is a powerful analytical method since real-time qualitative and quantitative detection of different sulfur and lithium species is crucial for understanding the electrochemical process in sulfur batteries. The first time, a combination of in operando lithium and sulfur NMR spectroscopy is presented, providing new insights at the molecular level that are essential for accelerating the development of lithium-sulfur battery technologies. [1] H. Wang, N. Sa, et al., The Journal of Physical Chemistry C 2017, 121, 6011–6017. [2] J. B. Richter, et al., Chemical Communications 2019, 55, 6042–6045. [3] R. Bhattacharyya, et al., Nat Mater 2010, 9, 504–510. [4] A. B. Gunnarsdóttir, et al., J Mater Chem A Mater 2020, 8, 14975–14992. [5] R. Musio, in Annu Rep NMR Spectrosc, 2006, pp. 1–88. [6] L. A. Huff, et al., Surf Sci 2015, 631, 295–300.
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Bezdomnikov, Alexey A., Liudmila I. Demina, Lyudmila G. Kuz’mina, Galina V. Kostikova, Valeriy I. Zhilov e Aslan Yu Tsivadze. "Study of Lithium-Extraction Systems Based on Benzo-15-Crown-5 Ether and Alkylimidazolium-Based Ionic Liquid". Molecules 28, n. 3 (17 gennaio 2023): 935. http://dx.doi.org/10.3390/molecules28030935.
Testo completoAbstract (sommario):
The extraction of lithium from aqueous solutions of LiNTf2 and LiCl salts using benzo-15-crown-5 ether (B15C5) as an extractant in [C8mim][NTf2] ionic liquid was studied. The transition of the extractant into the aqueous phase and the distribution of Cl− ions during lithium extraction from LiCl solutions were determined. LiNTf2 complexes with B15C5 with different LiNTf2:B15C5 ratios were isolated for the first time and characterized via X-ray diffraction and IR spectroscopy. Differences in the extraction process of LiCl and LiNTf2 were determined via an infrared spectroscopic study of the extraction systems.
10
Jin, Yan, Lin Zhou, Jianyu Yu, Jie Liang, Wenshan Cai, Huigang Zhang, Shining Zhu e Jia Zhu. "In operando plasmonic monitoring of electrochemical evolution of lithium metal". Proceedings of the National Academy of Sciences 115, n. 44 (15 ottobre 2018): 11168–73. http://dx.doi.org/10.1073/pnas.1808600115.
Testo completoAbstract (sommario):
The recent renaissance of lithium metal batteries as promising energy storage devices calls for in operando monitoring and control of electrochemical evolution of lithium metal morphologies. While the development of plasmonics has led to significant advancement in real-time and ultrasensitive chemical and biological sensing and surface-enhanced spectroscopies, alkali metals featured by ideal free electron gas models have long been regarded as promising plasmonic materials but seldom been explored due to their high chemical reactivity. Here, we demonstrate the in operando plasmonic monitoring of the electrochemical evolution of lithium metal during battery cycling by taking advantage of selective electrochemical deposition. The relationships between the evolving morphologies of lithium metal and in operando optical spectra are established both numerically and experimentally: Ordered growth of lithium particles shows clear size-dependent reflective dips due to hybrid surface plasmon resonances, while the formation of undesirable disordered lithium dendrites exhibits a flat spectroscopic profile with pure suppression in reflection intensity. Under the in operando plasmonic monitoring enabled by the microscopic morphology of metal, the differences of lithium evolutionary behaviors with different electrolytes can be conveniently identified without destruction. At the intersection of energy storage and plasmonics, it is expected that the ability to actively control and in operando plasmonically monitor electrochemical evolution of lithium metal can provide a promising platform for investigating lithium metal behavior during electrochemical cycling under various working conditions.
11
Yildiz, Aysegul. "Phosphoinositide metabolism, lithium and manic depressive illness". Spectroscopy 16, n. 3-4 (2002): 307–16. http://dx.doi.org/10.1155/2002/535201.
Testo completoAbstract (sommario):
Physiology underlying manic depressive illness and treating effects of its most commonly used remedy – “lithium” is yet to be elucidated. Recent years of psychopharmacology research witnessed sparkling developments in our understanding of the mechanisms underlying lithium’s mood stabilizing effects. Recent data on molecular biology andin vivomagnetic resonance spectroscopy suggest that some of the initial actions of lithium may occur through the inhibition of the enzyme inositol monophosphatase (IMPase) and reduction ofmyo–inositol, which in turn initiate a cascade of events at different levels of signal transduction process and gene expression in brain; such as the effects on protein kinase C, myristoylated alenine rich C kinase substrate protein, glycogen synthase kinase 3β, B cell lymphoma–2 protein, and activator protein–I. It is likely that the enzyme IMPase other that being the key point in initiating lithium’s therapeutic effects, may also play a critical role in the physiology underlying manic depressive illness.
12
Mott, A., M. Steffen, E. Caffau e K. G. Strassmeier. "Improving spectroscopic lithium abundances". Astronomy & Astrophysics 638 (giugno 2020): A58. http://dx.doi.org/10.1051/0004-6361/201937047.
Testo completoAbstract (sommario):
Context. Accurate spectroscopic lithium abundances are essential in addressing a variety of open questions, such as the origin of a uniform lithium content in the atmospheres of metal-poor stars (Spite plateau) or the existence of a correlation between the properties of extrasolar planetary systems and the lithium abundance in the atmosphere of their host stars. Aims. We have developed a tool that allows the user to improve the accuracy of standard lithium abundance determinations based on 1D model atmospheres and the assumption of local thermodynamic equilibrium (LTE) by applying corrections that account for hydrodynamic (3D) and non-LTE (NLTE) effects in FGK stars of different metallicity. Methods. Based on a grid of CO5BOLD 3D models and associated 1D hydrostatic atmospheres, we computed three libraries of synthetic spectra of the lithium λ 670.8 nm line for a wide range of lithium abundances, accounting for detailed line formation in 3D NLTE, 1D NLTE, and 1D LTE, respectively. The resulting curves-of-growth were then used to derive 3D NLTE and 1D NLTE lithium abundance corrections. Results. For all metallicities, the largest corrections are found at the coolest effective temperature, Teff = 5000 K. They are mostly positive, up to + 0.2 dex, for the weakest lines (lithium abundance A(Li)1DLTE = 1.0), whereas they become more negative towards lower metallicities, where they can reach − 0.4 dex for the strongest lines (A(Li)1DLTE = 3.0) at [Fe/H] = − 2.0. We demonstrate that 3D and NLTE effects are small for metal-poor stars on the Spite plateau, leading to errors of at most ± 0.05 dex if ignored. We present analytical functions evaluating the 3D NLTE and 1D NLTE corrections as a function of Teff [5000…6500 K], log g [3.5…4.5], and LTE lithium abundance A(Li) [1.0…3.0] for a fixed grid of metallicities [Fe∕H] [ − 3.0…0.0]. In addition, we also provide analytical fitting functions for directly converting a given lithium abundance into an equivalent width, or vice versa, a given equivalent width (EW) into a lithium abundance. For convenience, a Python script is made available that evaluates all fitting functions for given Teff, log g, [Fe∕H], and A(Li) or EW. Conclusions. By means of the fitting functions developed in this work, the results of complex 3D and NLTE calculations are made readily accessible and quickly applicable to large samples of stars across a wide range of metallicities. Improving the accuracy of spectroscopic lithium abundance determinations will contribute to a better understanding of the open questions related to the lithium content in metal-poor and solar-like stellar atmospheres.
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Pagot, Gioele, Sara Tonello, Keti Vezzù e Vito Di Noto. "A New Glass-Forming Electrolyte Based on Lithium Glycerolate". Batteries 4, n. 3 (1 settembre 2018): 41. http://dx.doi.org/10.3390/batteries4030041.
Testo completoAbstract (sommario):
The detailed study of the interplay between the physicochemical properties and the long-range charge migration mechanism of polymer electrolytes able to carry lithium ions is crucial in the development of next-generation lithium batteries. Glycerol exhibits a number of features (e.g., glass-forming behavior, low glass transition temperature, high flexibility of the backbone, and efficient coordination of lithium ions) that make it an appealing ion-conducting medium and a challenging building block in the preparation of new inorganic–organic polymer electrolytes. This work reports the preparation and the extensive investigation of a family of 11 electrolytes based on lithium glycerolate. The electrolytes have the formula C3H5(OH)3−x(OLi)x, where 0 ≤ x ≤ 1. The elemental composition is evaluated by inductively coupled plasma atomic emission spectroscopy. The structure and interactions are studied by vibrational spectroscopies (FT-IR and micro-Raman). The thermal properties are gauged by modulated differential scanning calorimetry and thermogravimetric analysis. Finally, insights on the long-range charge migration mechanism and glycerol relaxation events are investigated via broadband electrical spectroscopy. Results show that in these electrolytes, glycerolate acts as a large and flexible macro-anion, bestowing to the material single-ion conductivity (1.99 × 10−4 at 30 °C and 1.55 × 10−2 S∙cm−1 at 150 °C for x = 0.250).
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Grünzel, Tobias, Young Joo Lee, Karsten Kuepper e Julien Bachmann. "Preparation of electrochemically active silicon nanotubes in highly ordered arrays". Beilstein Journal of Nanotechnology 4 (16 ottobre 2013): 655–64. http://dx.doi.org/10.3762/bjnano.4.73.
Testo completoAbstract (sommario):
Silicon as the negative electrode material of lithium ion batteries has a very large capacity, the exploitation of which is impeded by the volume changes taking place upon electrochemical cycling. A Si electrode displaying a controlled porosity could circumvent the difficulty. In this perspective, we present a preparative method that yields ordered arrays of electrochemically competent silicon nanotubes. The method is based on the atomic layer deposition of silicon dioxide onto the pore walls of an anodic alumina template, followed by a thermal reduction with lithium vapor. This thermal reduction is quantitative, homogeneous over macroscopic samples, and it yields amorphous silicon and lithium oxide, at the exclusion of any lithium silicides. The reaction is characterized by spectroscopic ellipsometry for thin silica films, and by nuclear magnetic resonance and X-ray photoelectron spectroscopy for nanoporous samples. After removal of the lithium oxide byproduct, the silicon nanotubes can be contacted electrically. In a lithium ion electrolyte, they then display the electrochemical waves also observed for other bulk or nanostructured silicon systems. The method established here paves the way for systematic investigations of how the electrochemical properties (capacity, charge/discharge rates, cyclability) of nanoporous silicon negative lithium ion battery electrode materials depend on the geometry.
15
Gomes, Luisa Larissa Arnaldo, Victor Sanctis, Huidong Dai e Sanjeev Mukerjee. "Shedding Light on Lithium-Sulfur Battery Dynamics: Real-Time Insights through in-Situ UV-Vis Spectroscopy on Modified Lab Equipment". ECS Meeting Abstracts MA2024-01, n. 53 (9 agosto 2024): 2773. http://dx.doi.org/10.1149/ma2024-01532773mtgabs.
Testo completoAbstract (sommario):
In current post-lithium-ion research, the focus is directed toward Lithium-Sulfur (Li-S) batteries, motivated by their outstandingly high energy density (2640 Wh/kg) and the widespread availability of sulfur in the Earth's crust. Moreover, in-situ UV-Vis spectroscopy has proven to be instrumental, allowing for the real-time observation of alterations in the chemical composition of various battery components during operational cycles [1,2]. Our current study delves into the influence of solvent selection, particularly donor and acceptor numbers, in formulating gel polymer electrolytes for Lithium-Sulfur batteries. Leveraging in-situ UV-Vis spectroscopy, our research provides real-time insights into dynamic interactions within the gel during battery operation, shedding light on evolving electrochemical processes. Systematically analyzing the impact of solvent properties on gel characteristics reveals a meaningful relationship, underscoring the importance of tailored solvent selection for optimizing gel performance. Moreover, this technique tracks polysulfide behavior, offering a comprehensive understanding of the gel's role in mitigating polysulfide shuttling. Notably, our study introduces a novel dimension by employing a custom-built in-situ UV-Vis cell featuring 3D-printed components, enhancing the versatility and applicability of these spectroscopic techniques in probing intricate interactions within gel polymer electrolytes. Moreover, by combining the UV-Vis results with Nuclear Magnetic Resonance and FTIR, we aim to advance fundamental knowledge and provide a pathway for optimizing battery performance and mitigating degradation mechanisms. References 1- Patel, Manu UM, Rezan Demir‐Cakan, Mathieu Morcrette, Jean‐Marie Tarascon, Miran Gaberscek, and Robert Dominko. "Li‐S Battery Analyzed by UV/Vis in Operando Mode." ChemSusChem 6, no. 7 (2013): 1177-1181. 2- He, Qi, Anna TS Freiberg, Manu UM Patel, Simon Qian, and Hubert A. Gasteiger. "Operando identification of liquid intermediates in lithium–sulfur batteries via transmission UV–vis spectroscopy." Journal of The Electrochemical Society 167, no. 8 (2020): 080508.
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HUANG Yi, 黄毅, 吴侃 WU Kan, 肖泽宇 XIAO Zeyu, 李铁映 LI Tieying, 蔡明璐 CAI Minglu e 陈建平 CHEN Jianping. "基于调制光频梳的薄膜铌酸锂波导超连续谱研究". ACTA PHOTONICA SINICA 52, n. 5 (2023): 0552221. http://dx.doi.org/10.3788/gzxb20235205.0552221.
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Reich, Hans J., e Wesley L. Whipple. "Mechanism of the lithiumiodine exchange in an iodothiophene". Canadian Journal of Chemistry 83, n. 9 (1 settembre 2005): 1577–87. http://dx.doi.org/10.1139/v05-173.
Testo completoAbstract (sommario):
Solutions of 2-lithio-5-methylthiophene (4) were characterized using DNMR techniques and shown to be a mixture of monomer and dimer in THFEt2O (3:2). The hypervalent iodine ate complex 5 (Ar2ILi+), a presumed intermediate in the LiI exchange with 2-iodo-5-methylthiophene, was observed by 13C and 7Li NMR spectroscopy at low temperatures (130 °C). At higher temperatures, the ate complex coalesced with 2-lithio-5-methylthiophene. A kinetic scheme was developed, which accounts for the exchange of the monomer 4M, dimer 4D, and 2-iodo-5-methylthiophene (6) with the ate complex 5. The rates of the various exchanges were obtained through a DNMR analysis of the variable temperature 13C and 7Li NMR spectra, and the thermodynamic and activation parameters were calculated. The monomer 4M and the ate complex 5 have similar reactivity as aryl donors in the LiI exchange reaction, but 4M is at least 1000 times as reactive as the dimer 4D towards the iodide.Key words: halogenmetal exchange, lithium iodinate, iodine ate complex, lithium reagent, aggregate reactivity.
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Meierl, Julia, e Ingo Krossing. "Conductivity Improvement of LiBF4 Containing Electrolyte for Enhanced Application in Lithium-Ion Batteries". ECS Meeting Abstracts MA2023-02, n. 65 (22 dicembre 2023): 3081. http://dx.doi.org/10.1149/ma2023-02653081mtgabs.
Testo completoAbstract (sommario):
In view of a possible cost reduction and safety improvement of Lithium-Ion-Batteries (LIBs), the exchangeability of the common electrolyte salt lithium hexafluorophosphate LiPF6 with lithium tetrafluoroborate LiBF4 was investigated.[1,2] Replacement of LiPF6 with LiBF4 was considered due to the salt’s superior thermal stability and moisture stability compared to LiPF6. While LiBF4 was repeatedly studied for application in LIBs, low conductivity compared to analogous electrolyte solutions with LiPF6 is referred to as one of the main drawbacks of LiBF4 electrolytes.[1,3] These differences in electrolyte solution conductivity are usually related to an increased tendency for ion pair formation between the [BF4]– anion and Li+.[1,4] To overcome the strong ion-pairing between Li+ and [BF4]–, the conductivity of a LiBF4 electrolyte solution was improved by introduction of different amounts of 1,2-dimethoxyethane (DME) as bidentate ligand into the commercially available electrolyte solvent L57 (ethyl carbonate : ethylmethyl carbonate, 30 : 70, by wt%). The solvent modification was carried out in consideration of the published superior oxidative stability of lithium associated oligoethers compared to non-associated analogues.[5] All electrolyte solutions were investigated for their electrochemical behavior and their performance in Lithium-Ion-Battery (LIB) cells with commercially available cell components. All results were referred to analogous measurements with LiPF6 and LiBF4 electrolyte solution in the unmodified L57 solvent. Electrochemical characterization was performed by conductivity measurements and cyclic voltammetry. Battery cell experiments were carried out for Lithium-Metal cells with excess of electrolyte solution and Lithium-Ion cells. Lithium nickel cobalt manganese oxide (NCM622) electrodes were implemented as positive electrodes and Lithium-Ion cells were assembled with graphite electrodes as negative electrodes. All battery cells were investigated for their ambient temperature cycle life. Furthermore, ambient temperature C-rate stability of Li-Ion cells was examined. In view of the electrochemical behavior, conductivity of LiBF4 electrolytes significantly increases with the introduction of DME to the chosen electrolyte solvent, which is shown in the figure presenting the temperature dependent conductivities of the investigated electrolyte solutions. This conductivity enhancement is decreasing towards the contribution of more than two equivalents of DME per Li+ ion in the electrolyte solution. Cyclic voltammetry experiments of the electrolyte solutions show negligible effects on reductive stability of the electrolyte solution system, while the respective oxidative stability distinctly decreases with the addition of DME into the electrolyte solvent. A decreased oxidative stability is considered to induce parasitic reactions at the positive electrode, which presumably can be affected by change of positive electrode material. Despite the differences in conductivity, battery cell experiments present LiBF4 as a comparable electrolyte salt to LiPF6, with a performance difference that could possibly be overcome by utilization of the right electrolyte additive(s). The investigated oligoether containing electrolyte solutions show inferior battery performance compared to the unmodified carbonate-based electrolyte solvent. Since the battery cycling experiments were prepared at the oxidative stability limit of these electrolyte solutions, these electrolyte solutions might still create promising battery cell performance with a change of positive electrode material. In order to further investigate the ion pair association of lithium cations and tetrafluoroborate anions, the utilized system was additionally investigated spectroscopically and with quantum chemical calculations on the basis of density functional theory. Spectroscopic characterization was carried out with help of stimulated spin echo experiments in nuclear magnetic spectroscopy and Raman spectroscopy measurements. Both spectroscopies present changes in the associated structure of lithium cation and tetrafluoroborate anions by addition of DME to the commercial electrolyte solvent. For further conclusions, these results were compared with the calculations prepared for the electrolyte solution system. In summary, spectroscopic characterization and quantum chemical calculations indicate a modification of the associated structures in solution by the addition of DME to the chosen electrolyte solvent. By comparison of all collected results, research concerning the application of LiBF4 electrolytes should be continued with adaption of electrolyte solution additives or positive electrode material, respectively. [1] C. Daniel, J. O. Besenhard (Hrsg.) Handbook of battery materials, Wiley-VCH-Verl., Weinheim, 2011. [2] M. Winter, R. J. Brodd, Chem. Rev. 2004, 104, 4245. [3] R. Korthauer (Hrsg.) Handbuch Lithium-Ionen-Batterien, Springer Vieweg, Berlin, Heidelberg, 2013. [4] H. Tsunekawa, A. Narumi, M. Sano, A. Hiwara, M. Fujita, H. Yokoyama, J. Phys. Chem. B 2003, 107, 10962. [5] K. Yoshida, M. Nakamura, Y. Kazue, N. Tachikawa, S. Tsuzuki, S. Seki, K. Dokko, M. Watanabe, J. Am. Chem. Soc. 2011, 133, 13121. Figure 1
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Biddinger, Elizabeth J., Michael Keating, Elijah Bernard, Sharon Lall-Ramnarine e Robert J. Messinger. "Ionic Liquid - Glyme Mixtures to Modify Solvation Chemistry, Electrochemical and Physiochemical Properties in Lithium Containing Electrolytes". ECS Meeting Abstracts MA2023-02, n. 56 (22 dicembre 2023): 2728. http://dx.doi.org/10.1149/ma2023-02562728mtgabs.
Testo completoAbstract (sommario):
Pyrrolidinium-based ionic liquids are an intriguing material for lithium-based battery electrolytes due to their inherit non-flammability and large electrochemical windows. Poor lithium-ion transport in ionic liquid-based electrolytes hinder the effectiveness of these electrolytes. Solvate ionic liquids were introduced as a subclass of ionic liquids consisting of high concentrations of lithium salts and glymes. For example, the solvate ionic liquid Li(G4)TFSI is an equimolar ratio of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and tetraethylene glycol dimethyl ether (G4). In this work, pyrrolidinium-based ionic liquids containing short polyether side chains, structurally analogous to glymes, are mixed with equimolar amounts of LiTFSI and varying portions of G4. These tertiary mixtures were evaluated based on the ratio of solvating oxygen to lithium ion ([O]/[Li+]) present in the mixture. Trends in the oxidative stability, conductivity and lithium transference number were evaluated from mixtures of [O]/[Li+] between 5 to 8. Oxidative stability of tertiary mixtures with [O]/[Li+] = 5 showed improved oxidative stability compared to the binary Li(G4)TFSI, while [O]/[Li+] > 5 had diminished oxidative stability. DSC thermal analysis between -85°C to +120°C showed the tertiary mixtures helped suppress the glass transition temperature of Li(G4)TFSI to lower temperatures. Changes in the solvation structures were evaluate using spectroscopic analysis, including Raman spectroscopy. The changes in the solvation chemistry were correlated to the physiochemical and electrochemical properties.
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Zhang, Shuoshuo, e John Thomas Sirr Irvine. "Characterisation of Molten Lithium Carbonate Corrosion on SiC Heating Elements Using Raman Spectroscopy". ECS Meeting Abstracts MA2023-02, n. 11 (22 dicembre 2023): 1065. http://dx.doi.org/10.1149/ma2023-02111065mtgabs.
Testo completoAbstract (sommario):
The synthesis of lithium battery materials involves the use of muffle furnaces operating with SiC type heating elements. Usually, the industrial SiC heating element is protected by passive oxidation forming a protective silica film on the surface of the element. However, this strategy is not suitable for heating elements that operate in a Li-rich environment. A preliminary study has recently been completed to develop an understanding on the degradation of silicon carbide heating elements under the exposure to lithia. After basic characterisation of the SiC rod and its oxidation in air, its reaction products in the presence of Li was studied. The SiC rod was reacted with a likely Li source, Li2CO3, in three different % Li concentration environments through vapour-phase, wetting and full-immersion studies, particularly at the temperature just above the Li2CO3 melting point in delivering accelerated ageing. The characterisation was achieved via an integrative data analysis through the coordination of Raman, XRD, and Energy dispersive X-ray analysis (EDX) techniques. We found that molten Li2CO3 reacts with the silica surface layer of the element forming three main lithium silicates (LixSiyOx/2+2y). The degradation of surface silica into non-adherent lithium silicate leads to a speeding-up of the SiC oxidation process. Both processes eventually lead to a complete structural failure of the SiC rod. We performed a long-term vapour phase lithium attack experiment characterising the SiC after regular time intervals solely by Raman spectroscopy. Initially, a library of Raman spectra for the commonly encountered compounds in the Si-Li-O system was obtained from specifically synthesised stoichiometric compounds. In doing so, the reaction products at different reaction time intervals can be clearly identified, demonstrating the utility of Raman characterisation in corrosion studies.
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Brooks, P., MJ Gallagher e A. Sarroff. "Organophosphorus Intermediates. IX. The Cleavage of α,ω-Bisdiphenylphosphinoalkanes With Lithium. A 13P N.M.R. Study". Australian Journal of Chemistry 40, n. 8 (1987): 1341. http://dx.doi.org/10.1071/ch9871341.
Testo completoAbstract (sommario):
The title phosphines, Ph2P(CH2).PPh2 (n = 2-5), react with lithium in tetrahydrofuran to give the corresponding 1, n-dilithio-1, n-di(phenylphosphines) directly with little or no intermediacy of the 1-lithio- 1-phenyl- n- diphenylphosphinoalkanes which can, however, be obtained by arylation of the diphosphides. Methylenebisdiphenylphosphine and 1,4-diphenyl-1,4-diphosphinane undergo exclusive phosphorus-alkyl carbon cleavage. The chemistry and 31P n.m.r. spectroscopy of the diphosphides are described and the mechanism of the cleavage reaction is discussed. Some cleavage reactions in liquid ammonia are described.
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Vargas-Barbosa, Nella Marie, Sebastian Puls e Henry Michael Woolley. "Hybrid Material Concepts for Thiophosphate-Based Solid-State Batteries". ECS Meeting Abstracts MA2023-01, n. 6 (28 agosto 2023): 984. http://dx.doi.org/10.1149/ma2023-016984mtgabs.
Testo completoAbstract (sommario):
Solid-state batteries (SSBs) could replace conventional lithium-ion batteries due to the possibility of increasing the energy density of the cells by using lithium metal as the anode material.[1] Among the many electrolyte candidates for lithium SSBs, the lithium thiophosphates are particularly interesting due to their high ionic conductivities at room temperature (>1 mS/cm). However, the (electro)chemical stability of these solid electrolytes is limited and not fully compatible with state-of-the-art high-potential cathode active materials[2] or the lithium metal anode.[3] At the cell level, the formation of interparticle voids between the various battery components (solid electrolyte, cathode active material, anode material, additives, decomposition interphases) hinder the net transport during cycling. To address the latter electro-chemo-mechanical challenges, we are exploring hybrid material approaches, in which we combine established materials (solid electrolytes, liquid electrolytes and/or polymer additives) with state-of-the-art cathode active materials and test their electrochemical performance in solid-state battery (half-)cells. Such cycling results are complimented by detailed electrochemical transport studies in symmetrical cells using DC polarization and electrochemical impedance spectroscopy, including transmission-line modeling. ex.situ chemically-specific spectroscopic methods are used to support our hypotheses and interpretation of the electrochemical results. Taken together, we attain a better picture on the positive (or negative) role hybrid materials play in SSBs. In this talk, we will showcase two hybrid systems, namely ionic liquid/thiophosphate lithium hybrid electrolytes and conductive polymers additives in NMC-based catholyte composites for Li6PS5Cl cells. The first part of the talk we will discuss the results in which we evaluate the performance of liquid electrolyte-solid electrolyte materials against lithium metal using galvanostatic electrochemical impedance spectroscopy. In the second part, we elucidate the partial ionic and electronic transport in polymer electrolyte-Li6PS5Cl-NMC catholytes as a function of polymer content using impedance spectroscopy and its effect in the cycling performance, both the stability as well as the magnitude of the discharge capacities. These systems serve as a good starting point for the further development and incorporation of hybrid materials in SSBs. Literature: [1] W. G. Zeier and J. Janek Nature Energy, 2016, 1, 16141. [2] G.F. Dewald, S. Ohno, M.A. Kraft, R. Kroever, P. Till, N.M. Vargas-Barbosa, J. Janek, W.G. Zeier Chem. Mater. 2019, 31, 8328. [3] L. M. Riegger, R. Schlem, J. Sann, W. G. Zeier, J. Janek, Angew. Chem. Int Ed 2021, 60, 6718. Figure 1
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Damri, Odeya, Nofar Shemesh e Galila Agam. "Is There Justification to Treat Neurodegenerative Disorders by Repurposing Drugs? The Case of Alzheimer’s Disease, Lithium, and Autophagy". International Journal of Molecular Sciences 22, n. 1 (27 dicembre 2020): 189. http://dx.doi.org/10.3390/ijms22010189.
Testo completoAbstract (sommario):
Lithium is the prototype mood-stabilizer used for acute and long-term treatment of bipolar disorder. Cumulated translational research of lithium indicated the drug’s neuroprotective characteristics and, thereby, has raised the option of repurposing it as a drug for neurodegenerative diseases. Lithium’s neuroprotective properties rely on its modulation of homeostatic mechanisms such as inflammation, mitochondrial function, oxidative stress, autophagy, and apoptosis. This myriad of intracellular responses are, possibly, consequences of the drug’s inhibition of the enzymes inositol-monophosphatase (IMPase) and glycogen-synthase-kinase (GSK)-3. Here we review lithium’s neurobiological properties as evidenced by its neurotrophic and neuroprotective properties, as well as translational studies in cells in culture, in animal models of Alzheimer’s disease (AD) and in patients, discussing the rationale for the drug’s use in the treatment of AD.
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Tezcan, Tugba, Banu Sezer, Ugur Tamer e Ismail Hakki Boyaci. "Rapid and Reliable Detection of Lithium in Water Sources Using Surface Enhanced Laser Induced Breakdown Spectroscopy (SENLIBS) on Aluminium Substrate". International Journal of Engineering and Technology 15, n. 1 (febbraio 2023): 17–21. http://dx.doi.org/10.7763/ijet.2023.v15.1212.
Testo completoAbstract (sommario):
Lithium is one of the most important materials in re-chargeable battery as well as pharmaceutical and automotive industry. Due to the increasing demand for lithium for industrial production and daily usage, the reliable detection and recovery of lithium, a non-renewable metal, from water resources is an essential requirement. In this work, we performed lithium detection using surface enhanced laser induced breakdown spectroscopy on aluminium (Al) substrate for three different matrices, sea, river and municipal water. We also examined the matrix effect on sensitivity of lithium detection. Lithium spiked samples in different concentration (0- 100 ppm) was dried on an Al surface. The specific emission line of Li 670 nm was used for quantitative analysis. The intensity of Li was obtained about 15 times on Al substrate better than microscope glass. The limit of detection (LOD) value achieved to 0.138 ppm. No significant matrix effect was observed in the different water sources. Good reliability was obtained for intra and inter-day precision methods with RSD is <3.7% and<7.3% respectively in all water samples. Total analysis time including sample preparation is approximately in 1 min. We demonstrated that SENLIBS method provides rapid, high accuracy and repeatability of sensitive Li detection in different water sources.
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Wu, Zhiyun, Hellmut Eckertb, Bernd D. Moselb, Manfred H. Möllera e Rainer Pöttgena. "Magnetic and Spectroscopic Properties of LiAuSn". Zeitschrift für Naturforschung B 58, n. 6 (1 giugno 2003): 501–4. http://dx.doi.org/10.1515/znb-2003-0602.
Testo completoAbstract (sommario):
The stannide LiAuSn was synthesized by reaction of the elements in a sealed tantalum tube. Magnetic susceptibility measurements reveal Pauli paramagnetism. LiAuSn shows a single 119Sn Mössbauer signal at an isomer shift of 2.12(3) mm/s subject to a quadrupole splitting of 1.51(2) mm/s. The 119Sn MAS NMR spectrum reveals a strong Knight shift of 5183 ppm, The unique lithium site present in the crystal structure is reflected by a single 7Li NMR signal at 9.8 ppm. While a significant shift of this resonance towards larger frequencies at higher temperature indicates that the s-spin density at the lithium sites increases with increasing temperatures, no motional narrowing occurs up to 470 K. This result indicates that the lithium ions are immobile on the NMR timescale within the temperature range observed.
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Abdelghany, A. M. "Structural and physical studies of PVC/PVDF doped Nano lithium salt for electrochemical applications". JOURNAL OF ADVANCES IN PHYSICS 13, n. 3 (29 marzo 2017): 4718–25. http://dx.doi.org/10.24297/jap.v13i3.5817.
Testo completoAbstract (sommario):
 AbstractPolymer blend of poly (vinyl chloride) and poly(vinylidene fluoride) of nominal composition (30PVC/70PVDF) wt:wt were prepared in the form of thin films using casting technique. Samples of the same composition doped with gradient concentration of nano lithium salt (LTO) were prepared and studied. Proposed filler was characterized using Fourier transform infrared spectroscopy (FTIR), UV/vis. optical absorption, X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Electron diffraction (ED). Obtained data approve the crystalline nano structure of filler with a cubic structure of average size (25-30 nm). Prepared nano composites were then investigated using different spectroscopic methods. XRD reveals the amorphous nature of the base polymer blend with tendency for increase in crystallinity with increasing the content of lithium salt. FTIR shows a preservation of the main vibrational spectral bands in their position with small variation in the area and intensity of some spectral bands related to the interaction between polymer and filler.
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Petrenko, E. M., e V. A. Semenova. "Diagnostics of Advanced Power Intensive Power Sources Based on the Acoustic Spectroscopy Method". Herald of the Bauman Moscow State Technical University. Series Natural Sciences, n. 6 (99) (dicembre 2021): 121–27. http://dx.doi.org/10.18698/1812-3368-2021-6-121-127.
Testo completoAbstract (sommario):
Objective of this article is to develop a method for lithium chemical current sources diagnostics, which would ensure high reliability in assessing their technical state (primarily, the discharge degree) close to potentially achievable introduction of the acoustic spectroscopy method. Today, microcalorimetric studies and methods of impedance and noise spectroscopy make it possible to predict the lithium chemical current sources service life. However, implementation of the microcalorimetric studies result requires a lot of time accompanied by using stationary and large-size equipment, which is practically impossible in the autonomous conditions. Application of the impedance spectroscopy method provides satisfactory results only with high degrees of discharge. In the range of 0--30 %, it is very difficult to determine the discharge degree, since noticeable alteration in the correlate within its deviation from the mean value is missing. In this regard, it is proposed in order to provide diagnostics of the lithium chemical current sources in the region of initial degrees of discharge to introduce the noise diagnostics method. In order to increase reliability of the diagnostic estimates, it is advisable to use acoustic spectroscopy as a physically independent method in diagnosing the state of lithium chemical current sources. Results of the preliminary measurements analysis confirm the prospects of using the acoustic spectroscopy method in assessing the current state of primary lithium chemical current sources. Experimental studies of the lithium chemical current sources response to acoustic (mechanical) action made it possible to determine a set of parameters characterizing the proposed methodological approach. This provided a possibility to search for correlation dependences of the lithium chemical current sources spectral characteristics on the degree of their discharge. This makes it possible to use the method of acoustic spectroscopy in prompt and reliable diagnostics of the primary current sources in the region of low discharge degrees
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Thanh Nguyen, Huynh Le. "HYDROTHERMAL SYNTHESIS OF NANO BILAYERED V2O5 AND ELECTROCHEMICAL BEHAVIOR IN NON–AQUEOUS ELECTROLYTES LiPF6 AND NaClO4". Vietnam Journal of Science and Technology 55, n. 1B (23 marzo 2018): 24. http://dx.doi.org/10.15625/2525-2518/55/1b/12087.
Testo completoAbstract (sommario):
This work aimed to prepare bilayered V2O5 by hydrothermal route from vanadium (III) chloride (VCl3). According to XRD results, bilayered V2O5 showed a large interlayer spacing around 11.3 Å. The electrochemical properties of bilayered V2O5 were carried out by cyclic voltammetry and charge–discharge testing in non–aqueous electrolytes LiPF6 and NaClO4. The curves charge–discharge showed that mechanism of insertion/extraction of Li+ ions and Na+ ions were occurred on a solution solid without the phase transition. Moreover, specific capacity for lithium and sodium intercalation of bilayered V2O5 were found out 250 mAh/g and 200 mAh/g, respectively. The kinetic of lithium’s and sodium’s insertion was evaluated by the electrochemical impedance spectroscopy (EIS). The EIS results exhibited a stabilization of charge transfer in both case and a slow kinetic of sodium’s diffusion compared to lithium’s case due to the large ionic radius of sodium.
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Grisoni, V., F. Matteucci, D. Romano e X. Fu. "Evolution of lithium in the Milky Way halo, discs, and bulge". Monthly Notices of the Royal Astronomical Society 489, n. 3 (2 settembre 2019): 3539–46. http://dx.doi.org/10.1093/mnras/stz2428.
Testo completoAbstract (sommario):
Abstract In this work, we study the Galactic evolution of lithium by means of chemical evolution models in the light of the most recent spectroscopic data from Galactic stellar surveys. We consider detailed chemical evolution models for the Milky Way halo, discs, and bulge, and we compare our model predictions with the most recent spectroscopic data for these different Galactic components. In particular, we focus on the decrease of lithium at high metallicity observed by the AMBRE Project, the Gaia-ESO Survey, and other spectroscopic surveys, which still remains unexplained by theoretical models. We analyse the various lithium producers and confirm that novae are the main source of lithium in the Galaxy, in agreement with other previous studies. Moreover, we show that, by assuming that the fraction of binary systems giving rise to novae is lower at higher metallicity, we can suggest a novel explanation to the lithium decline at super-solar metallicities: the aforementioned assumption is based on independent constraints on the nova system birth rate, which have been recently proposed in the literature. As regards the thick disc, it is less lithium enhanced due to the shorter time-scale of formation and higher star formation efficiency with respect to the thin disc; therefore, we have a faster evolution and the ‘reverse knee’ in the A(Li) versus [Fe/H] relation is shifted towards higher metallicities. Finally, we present our predictions about lithium evolution in the Galactic bulge, which, however, still need further data to be confirmed or disproved.
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M, Selvamurugan, Dhilip Kumar R, Karthikeyan C e Karuppuchamy S. "SYNTHESIS AND CHARACTERIZATION OF LITHIUM TITANATE (LTO) NANOCOMPOSITES VIA SOLUTION GROWTH ROUTE FOR Li-ION BATTERIES". Kongunadu Research Journal 4, n. 3 (30 dicembre 2017): 10–13. http://dx.doi.org/10.26524/krj225.
Testo completoAbstract (sommario):
The novel bimetal oxide composite of Li4Ti5O12 was successfully synthesized by solution growth technique. The structural and microstructural properties of synthesized powders were characterized by powder X-ray diffraction (XRD), fourrier transform infrared spectroscopy (FT-IR), Raman spectroscopy,scanning electron microscopy (SEM) and energy dispersive X-ray-spectroscopy (EDX). The electrochemical performance of the Li4Ti5O12 anode was investigated using galvanostatic charge-discharge techniques. The electrochemical property of the Lithium titanate anode was investigated. The good electrochemicalperformance is ascribed to the stable lithium storage host structure, decreased electrochemical resistance and enhanced lithium-ion diffusion coefficient. Therefore, Li4Ti5O12 may be a promising alternative anode material for Li-ion batteries.
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Zhang, Ming, Yanshuo Liu, Dezhi Li, Xiaoli Cui, Licheng Wang, Liwei Li e Kai Wang. "Electrochemical Impedance Spectroscopy: A New Chapter in the Fast and Accurate Estimation of the State of Health for Lithium-Ion Batteries". Energies 16, n. 4 (5 febbraio 2023): 1599. http://dx.doi.org/10.3390/en16041599.
Testo completoAbstract (sommario):
Lithium-ion batteries stand out from other clean energy sources because of their high energy density and small size. With the increasing application scope and scale of lithium-ion batteries, real-time and accurate monitoring of its state of health plays an important role in ensuring the healthy and stable operation of an energy storage system. Due to the interaction of various aging reactions in the aging process of lithium-ion batteries, the capacity attenuation shows no regularity. However, the traditional monitoring method is mainly based on voltage and current, which cannot reflect the internal mechanism, so the accuracy is greatly reduced. Recently, with the development of electrochemical impedance spectroscopy, it has been possible to estimate the state of health quickly and accurately online. Electrochemical impedance spectroscopy can measure battery impedance in a wide frequency range, so it can reflect the internal aging state of lithium-ion batteries. In this paper, the latest impedance spectroscopy measurement technology and electrochemical impedance spectroscopy based on lithium-ion battery health state estimation technology are summarized, along with the advantages and disadvantages of the summary and prospects. This fills the gap in this aspect and is conducive to the further development of this technology.
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Fabre, Cécile, Nour Eddine Ourti, Julien Mercadier, Joana Cardoso-Fernandes, Filipa Dias, Mônica Perrotta, Friederike Koerting et al. "Analyses of Li-Rich Minerals Using Handheld LIBS Tool". Data 6, n. 6 (21 giugno 2021): 68. http://dx.doi.org/10.3390/data6060068.
Testo completoAbstract (sommario):
Lithium (Li) is one of the latest metals to be added to the list of critical materials in Europe and, thus, lithium exploration in Europe has become a necessity to guarantee its mid- to long-term stable supply. Laser-induced breakdown spectroscopy (LIBS) is a powerful analysis technique that allows for simultaneous multi-elemental analysis with an excellent coverage of light elements (Z < 13). This data paper provides more than 4000 LIBS spectra obtained using a handheld LIBS tool on approximately 140 Li-content materials (minerals, powder pellets, and rocks) and their Li concentrations. The high resolution of the spectrometers combined with the low detection limits for light elements make the LIBS technique a powerful option to detect Li and trace elements of first interest, such as Be, Cs, F, and Rb. The LIBS spectra dataset combined with the Li content dataset can be used to obtain quantitative estimation of Li in Li-rich matrices. This paper can be utilized as technical and spectroscopic support for Li detection in the field using a portable LIBS instrument.
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Liu, Xiaoming, Yan Chen, Zachary D. Hood, Cheng Ma, Seungho Yu, Asma Sharafi, Hui Wang et al. "Elucidating the mobility of H+ and Li+ ions in (Li6.25−xHxAl0.25)La3Zr2O12via correlative neutron and electron spectroscopy". Energy & Environmental Science 12, n. 3 (2019): 945–51. http://dx.doi.org/10.1039/c8ee02981d.
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Yan, T. S., J. R. Shi, L. Wang, H. L. Yan, Z. M. Zhou, Y. T. Zhou, X. S. Fang, C. Q. Li, T. Y. Chen e X. J. Xie. "Discovery of Nine Super Li-rich Unevolved Stars from the LAMOST Survey". Astrophysical Journal Letters 929, n. 1 (1 aprile 2022): L14. http://dx.doi.org/10.3847/2041-8213/ac63a5.
Testo completoAbstract (sommario):
Abstract Based on the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) medium-resolution spectroscopic survey (MRS), we report the discovery of nine super Li-rich unevolved stars with A(Li) > 3.8 dex. These objects show unusually high levels of lithium abundances, up to three times higher than the meteoritic value of 3.3 dex, which indicates that they must have experienced a history of lithium enrichment. It is found that seven of our program stars are fast rotators with v sin i > 9 km s−1, which suggests that the accretion of circumstellar matter may be the main contributor to the lithium enhancement of these unevolved stars; however, other sources cannot be excluded.
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Gomes, Luisa Larissa Arnaldo, Huidong Dai, Victor Sanctis e Sanjeev Mukerjee. "Operando Raman and in-Situ UV-Vis Spectroscopy Unveil the Impact of Solvent Donor and Acceptor Numbers on Gel Polymer Electrolytes in Lithium-Sulfur Batteries". ECS Meeting Abstracts MA2024-01, n. 2 (9 agosto 2024): 388. http://dx.doi.org/10.1149/ma2024-012388mtgabs.
Testo completoAbstract (sommario):
Lithium-sulfur (Li-S) batteries boast a specific capacity five times greater than current Li-intercalation systems. Still, practical implementation faces challenges tied to liquid electrolytes, i.e., lithium metal dendrites formation, polysulfide redox-shuttle, and flammability [1]. Thus, we focus on developing biodegradable gel polymer electrolytes to overcome these issues, fostering eco-friendly, safer, and more effective energy storage solutions. Polycaprolactone (PCL) emerges as a promising GPE candidate due to its biodegradable nature and broad stability range (~5V vs Li0/Li+). Our current study investigates the influence of solvent selection, explicitly focusing on donor and acceptor numbers, in formulating gel polymer electrolytes for Lithium-Sulfur batteries. Leveraging operando Raman and in-situ UV-Vis spectroscopy, our research provides real-time insights into the dynamic interactions within the gel during battery operation, shedding light on the evolving electrochemical processes. Moreover, by systematically analyzing the impact of solvent properties on gel characteristics, we reveal a nuanced relationship, emphasizing the importance of tailored solvent selection for optimizing gel performance. Operando Raman spectroscopy enables the observation of bond formations and structural changes in the gel, while in-situ UV-Vis spectroscopy tracks the behavior of polysulfides, facilitating the identification of specific interactions and offering a comprehensive understanding of the gel's role in mitigating polysulfide shuttling. This work aims to advance our fundamental knowledge of gel polymer electrolytes and provide a pathway for optimizing battery performance and mitigating degradation mechanisms. Notably, our study introduces a novel dimension by employing a custom-built UV-Vis setup, enhancing the versatility and applicability of these spectroscopic techniques in probing the intricate interactions within gel polymer electrolytes. Reference 1-Pervez, S. A.; Vinayan, B. P.; Cambaz, M. A.; Melinte, G.; Diemant, T.; Braun, T.; Karkera, G.; Behm, R. J.; Fichtner, M., Electrochemical and compositional characterization of solid interphase layers in an interface-modified solid-state Li–sulfur battery. Journal of Materials Chemistry A2020, 8 (32), 16451-16462.
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Gherardelli, Camila, Pedro Cisternas e Nibaldo C. Inestrosa. "Lithium Enhances Hippocampal Glucose Metabolism in an In Vitro Mice Model of Alzheimer’s Disease". International Journal of Molecular Sciences 23, n. 15 (5 agosto 2022): 8733. http://dx.doi.org/10.3390/ijms23158733.
Testo completoAbstract (sommario):
Impaired cerebral glucose metabolism is an early event that contributes to the pathogenesis of Alzheimer’s disease (AD). Importantly, restoring glucose availability by pharmacological agents or genetic manipulation has been shown to protect against Aβ toxicity, ameliorate AD pathology, and increase lifespan. Lithium, a therapeutic agent widely used as a treatment for mood disorders, has been shown to attenuate AD pathology and promote glucose metabolism in skeletal muscle. However, despite its widespread use in neuropsychiatric disorders, lithium’s effects on the brain have been poorly characterized. Here we evaluated the effect of lithium on glucose metabolism in hippocampal neurons from wild-type (WT) and APPSwe/PS1ΔE9 (APP/PS1) mice. Our results showed that lithium significantly stimulates glucose uptake and replenishes ATP levels by preferential oxidation of glucose through glycolysis in neurons from WT mice. This increase was also accompanied by a strong increase in glucose transporter 3 (Glut3), the major carrier responsible for glucose uptake in neurons. Similarly, using hippocampal slices from APP-PS1 mice, we demonstrate that lithium increases glucose uptake, glycolytic rate, and the ATP:ADP ratio in a process that also involves the activation of AMPK. Together, our findings indicate that lithium stimulates glucose metabolism and can act as a potential therapeutic agent in AD.
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Fedoseeva, Yuliya V., Elena V. Shlyakhova, Anna A. Makarova, Alexander V. Okotrub e Lyubov G. Bulusheva. "X-ray Spectroscopy Study of Defect Contribution to Lithium Adsorption on Porous Carbon". Nanomaterials 13, n. 19 (22 settembre 2023): 2623. http://dx.doi.org/10.3390/nano13192623.
Testo completoAbstract (sommario):
Lithium adsorption on high-surface-area porous carbon (PC) nanomaterials provides superior electrochemical energy storage performance dominated by capacitive behavior. In this study, we demonstrate the influence of structural defects in the graphene lattice on the bonding character of adsorbed lithium. Thermally evaporated lithium was deposited in vacuum on the surface of as-grown graphene-like PC and PC annealed at 400 °C. Changes in the electronic states of carbon were studied experimentally using surface-sensitive X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. NEXAFS data in combination with density functional theory calculations revealed the dative interactions between lithium sp2 hybridized states and carbon π*-type orbitals. Corrugated defective layers of graphene provide lithium with new bonding configurations, shorter distances, and stronger orbital overlapping, resulting in significant charge transfer between carbon and lithium. PC annealing heals defects, and as a result, the amount of lithium on the surface decreases. This conclusion was supported by electrochemical studies of as-grown and annealed PC in lithium-ion batteries. The former nanomaterial showed higher capacity values at all applied current densities. The results demonstrate that the lithium storage in carbon-based electrodes can be improved by introducing defects into the graphene layers.
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Aurbach, Doron, e Arie Zaban. "Impedance spectroscope of lithium electrodes". Journal of Electroanalytical Chemistry 367, n. 1-2 (marzo 1994): 15–25. http://dx.doi.org/10.1016/0022-0728(93)02998-w.
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Zheng, Yijing, Lisa Pfäffl, Hans Jürgen Seifert e Wilhelm Pfleging. "Lithium Distribution in Structured Graphite Anodes Investigated by Laser-Induced Breakdown Spectroscopy". Applied Sciences 9, n. 20 (10 ottobre 2019): 4218. http://dx.doi.org/10.3390/app9204218.
Testo completoAbstract (sommario):
For the development of thick film graphite electrodes, a 3D battery concept is applied, which significantly improves lithium-ion diffusion kinetics, high-rate capability, and cell lifetime and reduces mechanical tensions. Our current research indicates that 3D architectures of anode materials can prevent cells from capacity fading at high C-rates and improve cell lifespan. For the further research and development of 3D battery concepts, it is important to scientifically understand the influence of laser-generated 3D anode architectures on lithium distribution during charging and discharging at elevated C-rates. Laser-induced breakdown spectroscopy (LIBS) is applied post-mortem for quantitatively studying the lithium concentration profiles within the entire structured and unstructured graphite electrodes. Space-resolved LIBS measurements revealed that less lithium-ion content could be detected in structured electrodes at delithiated state in comparison to unstructured electrodes. This result indicates that 3D architectures established on anode electrodes can accelerate the lithium-ion extraction process and reduce the formation of inactive materials during electrochemical cycling. Furthermore, LIBS measurements showed that at high C-rates, lithium-ion concentration is increased along the contour of laser-generated structures indicating enhanced lithium-ion diffusion kinetics for 3D anode materials. This result is correlated with significantly increased capacity retention. Moreover, the lithium-ion distribution profiles provide meaningful information about optimizing the electrode architecture with respect to film thickness, pitch distance, and battery usage scenario.
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Pulst, Martin, Hossam Elgabarty, Daniel Sebastiani e Jörg Kressler. "The annular tautomerism of lithium 1,2,3-triazolate". New Journal of Chemistry 41, n. 4 (2017): 1430–35. http://dx.doi.org/10.1039/c6nj03732a.
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Rüter, Christian E., Dominik Brüske, Sergiy Suntsov e Detlef Kip. "Investigation of Ytterbium Incorporation in Lithium Niobate for Active Waveguide Devices". Applied Sciences 10, n. 6 (24 marzo 2020): 2189. http://dx.doi.org/10.3390/app10062189.
Testo completoAbstract (sommario):
In this work, we report on an investigation of the ytterbium diffusion characteristics in lithium niobate. Ytterbium-doped substrates were prepared by in-diffusion of thin metallic layers coated onto x- and z-cut congruent substrates at different temperatures. The ytterbium profiles were investigated in detail by means of secondary neutral mass spectroscopy, optical microscopy, and optical spectroscopy. Diffusion from an infinite source was used to determine the solubility limit of ytterbium in lithium niobate as a function of temperature. The derived diffusion parameters are of importance for the development of active waveguide devices in ytterbium-doped lithium niobate.
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Gnedenkov, Sergei Vasil'evich, Denis Pavlovich Opra, Sergei Leonidovich Sinebryukhov, Aleksandr Konstantinovich Tsvetnikov, Aleksandr Yur'evich Ustinov e Valentin Ivanovich Sergienko. "The lithium batteries based on the gidrolytic lignin". Electrochemical Energetics 13, n. 1 (2013): 23–33. http://dx.doi.org/10.18500/1608-4039-2013-13-1-23-33.
Testo completoAbstract (sommario):
In this paper the possibility of applying of hydrolysis lignin as the lithium battery cathode material was demonstrated for the first time. Hydrolysis lignin features have been investigated by impedance spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Electrochemical characterization was carried out at room temperature using 1M LiBF4 in γ-butyrolacton electrolyte system. The chemical composition of cathode materials upon battery discharge down to 0.9 V was studied by the X-ray photoelectron spectroscopy and Infrared spectroscopy. The suggestions on possible electrochemical reactions occurring in the lithium/hydrolysis lignin system were made on the basis of the products composition analysis.
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Arise, Ichiro, Yuto Miyahara, Kohei Miyazaki e Takeshi Abe. "Dendrite Growth of Lithium through Separator Using In Situ Measurement Technique". Journal of The Electrochemical Society 169, n. 2 (1 febbraio 2022): 020546. http://dx.doi.org/10.1149/1945-7111/ac52c4.
Testo completoAbstract (sommario):
In situ techniques as a clue to clarify the mechanism of lithium dendrite growth through the separator were applied. The aim of this work was to clarify the dendrite growth mechanism through the separator and to investigate and discuss the relationship between lithium intercalation into graphite and lithium deposition on the graphite surface, applying in situ and ex situ optical microscope and in situ electrochemical impedance spectroscopy. It was visually characterized the lithium dendrite growth by the ionic transfer through the separator and obtained the fundamental knowledge by in situ optical microscope. In the case of lithium deposition through the aramid coated separator (ACS), the dendrites were observed to be granular over a wide area. On the other hand, in the case of lithium deposition through the ceramic coated separator (CCS), dendrites were fibrous over a wide area by ex situ optical microscope. The superiority of ACS is related to the flatness and uniformity of the pores due to aramid resin. This result was supported by an analysis applying in situ electrochemical impedance spectroscopy.
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Li, Jie. "Towards Highly Efficient Lithium-Ion Batteries: Focusing on Electrolytes". Highlights in Science, Engineering and Technology 29 (31 gennaio 2023): 175–83. http://dx.doi.org/10.54097/hset.v29i.4553.
Testo completoAbstract (sommario):
Lithium-ion is various advantages and is required by batteries such as high power, so lithium-ion plays a crucial role in lithium-ion batteries. The electrolyte is one of the core materials of lithium secondary battery and primary battery capacity, improves the mobility between the mobile anode and cathode, and plays the role of medium material. The lithium-ion battery's electrolyte, a crucial component, transports ion conduction current between the positive and negative electrodes. Choosing the right electrolyte is also essential for achieving high energy and power densities, long cycle lives, and good safety performance of the lithium-ion secondary battery. First, understand the lithium-ion battery charge and discharge of the working principle of the chemical equation, and the lithium-ion battery is split into four key components, respectively: positive and negative electrode, diaphragm, and electrolyte, then the electrolyte analysis, the electrolyte is composed of organic solution, conductive salt, and additives. Finally, a new type of sulfate additive, ethyl sulfate, is found and studied at the electrolyte level by literature search. By using the constant current charge-discharge test, cyclic voltammetry, scanning electron microscopy, energy scattering spectroscopy, and electrochemical impedance spectroscopy, researchers are examining the effects of additive ethyl sulfate (DTD) on the performance of lithium-ion batteries and the interfacial performance of graphitized carbon microspheres (MCMB) electrode/electrolyte (EIS).
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Ni’mah, Y. L., S. Suprapto, H. A. Putri, F. K. Rahmah e A. Hardiansyah. "THE APPLICATION OF LiMn2O4 SYNTHESIZED FROM MANGANESE ORE FOR LITHIUM- ION BATTERIES CATHODE". RASAYAN Journal of Chemistry 15, n. 04 (2022): 2203–9. http://dx.doi.org/10.31788/rjc.2022.1546945.
Testo completoAbstract (sommario):
Lithium manganese oxide (LiMn2O4) synthesized from manganese ore has been successfully applied for cathode materials of lithium-ion batteries. LiMn2O4 was obtained by reacting lithium carbonate (Li2CO3) and manganese oxide (MnO2) using a solid-state reaction. The structure characterization of LiMn2O4 was carried out using X-ray diffraction (XRD) and Raman spectroscopy. The thermal properties of cathode material were studied using Thermal Gravimetric Analysis (TGA). The electrochemical properties were analyzed using cyclic voltammetry (CV), charge-discharge (CD), and electrochemical impedance spectroscopy (EIS). Two pairs of redox peaks were identified at 3.0-4.5 V. The efficiency of the battery was 94.74% in the first cycle with maximum electrical conductivity of 5.26 x 10-4 S cm-1. It was concluded that LiMn2O4 synthesized from manganese ore can be applied as the cathode of lithium-ion batteries.
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Perez, Israel, Victor Sosa, Fidel Gamboa, Jose Luis Enriquez-Carrejo e Juan Carlos Mixteco Sanchez. "Role of lithium intercalation in fluorine-doped tin oxide thin films: Ab initio calculations and experiment". Journal of Chemical Physics 156, n. 9 (7 marzo 2022): 094701. http://dx.doi.org/10.1063/5.0085531.
Testo completoAbstract (sommario):
Using a combination of experimental techniques and density functional theory (DFT) calculations, the influence of lithium insertion on the electronic and electrochemical properties of fluorine-doped SnO2 (FTO) is assessed. For this purpose, we investigate the electrochromic behavior of a commercial FTO electrode embedded in a solution of lithium perclorate (LiClO4). The electrochromic properties are evaluated by UV–vis spectroscopy, cyclic voltammetry, and chronoamperometry. These tests show that FTO exhibits electrochromism with a respectable coloration efficiency ( η = 47.9 cm2/C at 637 nm). DFT study indicates that lithium remains ionized in the lattice, raising the Fermi level about 0.7 eV deep into the conduction band. X-ray photoelectron spectroscopy (XPS) is used to study chemical bonding and oxidation states. XPS analysis of the Sn 3d core levels reveals that lithium insertion in FTO induces a shift of 350 meV in the Sn 3d states, suggesting that lithium is incorporated into the SnO2 lattice.
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Moritomo, Yutaka, Masamitsu Takachi, Yutaro Kurihara e Tomoyuki Matsuda. "Synchrotron-Radiation X-Ray Investigation of Li+/Na+Intercalation into Prussian Blue Analogues". Advances in Materials Science and Engineering 2013 (2013): 1–17. http://dx.doi.org/10.1155/2013/967285.
Testo completoAbstract (sommario):
Prussian blue analogies (PBAs) are promising cathode materials for lithium ion (LIB) and sodium ion (SIB) secondary batteries, reflecting their covalent and nanoporous host structure. With use of synchrotron-radiation (SR) X-ray source, we investigated the structural and electronic responses of the host framework of PBAs against Li+and Na+intercalation by means of the X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS). The structural investigation reveals a robust nature of the host framework against Li+and Na+intercalation, which is advantageous for the stability and lifetime of the batteries. The spectroscopic investigation identifies the redox processes in respective plateaus in the discharge curves. We further compare these characteristics with those of the conventional cathode materials, such as, LiCoO2, LiFePO4, and LiMn2O4.
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Charoy, Bernard, Marc Chaussidon e Fernando Noronha. "Lithium zonation in white micas from the Argemela microgranite (central Portugal): an in-situ ion-, electron-microprobe and spectroscopic investigation". European Journal of Mineralogy 7, n. 2 (29 marzo 1995): 335–52. http://dx.doi.org/10.1127/ejm/7/2/0335.
Testo completo
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Badilescu, Simona, Khalid Boufker, P. V. Ashrit, Fernand E. Girouard e Vo-Van Truong. "FT-IR/ATR Study of Lithium Intercalation into Molybdenum Oxide Thin Film". Applied Spectroscopy 47, n. 6 (giugno 1993): 749–52. http://dx.doi.org/10.1366/0003702934066866.
Testo completoAbstract (sommario):
Molybdenum oxide thin films are deposited by thermal evaporation and sputtering, and lithium is inserted by a dry lithiation method. The FT-IR/ATR technique is used to study the formation and evolution of lithium bronze and lithium molybdate species. The mechanism of lithium intercalation is found to be dependent on the method of film preparation. The involvement of water molecules in the kinetics of lithiation is stressed.
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Choi, Hyun Chul, Young Mee Jung e Seung Bin Kim. "Characterization of the Electrochemical Reactions in the Li1+xV3O8/Li Cell by Soft X-ray Absorption Spectroscopy and Two-Dimensional Correlation Analysis". Applied Spectroscopy 57, n. 8 (agosto 2003): 984–90. http://dx.doi.org/10.1366/000370203322258959.
Testo completoAbstract (sommario):
We applied soft X-ray absorption spectroscopy (XAS) and two-dimensional (2D) correlation analysis to the first lithium insertion–extraction cycle in a Li1+xV3O8/Li cell in order to investigate the electrochemical reactions of lithium with the Li1+xV3O8 electrode. The V LII,III-edge and O K-edge spectra of the Li1+xV3O8 electrode were obtained for varying electrode lithium content. The insertion of lithium leads to the reduction of the V5+ species present in the pristine Li1+xV3O8 electrode, and to the red shift and the broadening of the spectral features of the V LII,III edge compared to those of the pristine electrode. In the extraction process, the main spectral features at the highest value of the extraction of lithium show some differences compared to the features of the pristine electrode spectrum due to the residual lithium ions in the Li1+xV3O8 structure. The O K-edge spectra revealed that the insertion of lithium mainly affects the V 4sp–O 2p bonds and consequently induces a change in bonding geometry. The 2D correlation analysis of these spectra clearly shows that V–O bonds are significantly perturbed by the insertion–extraction of lithium into the Li1+xV3O8 electrode.