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Thermodynamic Effect of Anion Activity on Electrochemical Reactions Involving Li+ Ions in Room‐Temperature Ionic Liquids
Get PDFThe effect of Li+ concentration on the electrochemical reactions of Li metal and graphite electrodes was studied in aprotic ionic liquid (P13TFSA: N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)amide) – LiTFSA mixtures. The electrode potential of the Li metal was governed not only by the activity of the complex Li+ ions ([Li(TFSA)2]-), but also by the free-TFSA- anions, because the desolvation step of the complex Li+ ions needed to be considered. With increasing LiTFSA concentration, the electrode potential of the Li metal increased due to increasing [Li(TFSA)2]-activity and decreasing free-TFSA- activity in the electrolyte solutions, which was supported by Raman spectroscopy results. The Li+ intercalation reaction into the graphite electrode was also investigated. With increasing LiTFSA concentration, the onium cation (P13+) intercalation, which is a well-known side reaction without a desolvation step, was suppressed and reversible Li+ intercalation into the graphite electrode was observed
High Transference Number of Na Ion in Liquid-State Sulfolane Solvates of Sodium Bis(fluorosulfonyl)amide
Get PDFThe phase behavior, Na+ coordination structures, and transport and electrochemical properties of binary mixtures of NaN(SO2F)2 (NaFSA) and sulfolane (SL) solvent were investigated. The NaFSA and SL form stable solvates at molar ratios [NaFSA]/[SL] = 1/3 and 1/0.5, and there is a crystallinity gap in the range 1/1.6 ≤ [NaFSA]/[SL] ≤ 1/0.8. In the crystals of both NaFSA-(SL)3 and NaFSA-(SL)0.5, the solvent-bridged Na+−SL−Na+ and anion-bridged Na+−FSA−Na+ structures are formed. In the crystallinity gap, the mixtures remain liquid at room temperature and can be regarded as molten SL-solvates of NaFSA. The Raman spectra of the molten solvates suggest that the solvent- and anion-bridged structures are partially maintained even in the liquid. However, Na+ ions exchange the ligands (solvent and anion) dynamically in the liquids. This significantly affects the Na+ ion transport in the liquids under an anion-blocking condition. The Na+ ion transference numbers (tNa+) of molten solvates were estimated using symmetric Na/Na cells, and a molten solvate of [NaFSA]/[SL] = 1/1 exhibited a high tNa+ of 0.8. Charge and discharge tests of a Na/Na0.44MnO2 battery were performed with the molten solvate as the electrolyte. The rate capability of the battery was found to be significantly affected by tNa+ in the electrolyte
Perspective on the quantum vacuum in matter
Get PDFAn intriguing consequence of quantum field theory is that a vacuum is not an empty space; it is full of fluctuating electromagnetic fields, or virtual photons, corresponding to their zero-point energy, even though the average number of photons is zero. These short-lived vacuum fluctuations are behind some of the most fascinating physical processes in the universe, including spontaneous emission, the Lamb shift, and the Casimir force. Recent theories and experiments indicate that the properties of materials placed in photonic cavities may be altered, even in the complete absence of any external fields, through interaction with the fluctuating vacuum electromagnetic fields. Judicious engineering of the quantum vacuum surrounding the matter inside a cavity can lead to significant and nonintuitive modifications of electronic and vibrational states, producing a “vacuum-dressed” material. These exciting new ideas have stimulated discussions regarding the fundamental physics of vacuum–matter interactions and also broadened the scope of potential applications using zero-point fluctuations to engineer materials. This Perspective will first discuss recent experimental and theoretical developments on vacuum-modified condensed matter systems, which usually require the realization of the so-called ultrastrong light–matter coupling regime. Then, we will overview some of the most promising cavity designs for enhancing vacuum electromagnetic fields in materials with various energy scales. Finally, we will discuss urgent open questions and technical challenges to be solved in this emerging field
<Article>Background and Issues of Revision of Accounting Standards for Public Interest Corporations
Get PDFEvaluation of Uncertainty in Tropical Cyclone Genesis and Track Forecasts with Ensemble Prediction
Get PDF横浜国立大学博士（理学）Doctor of Scienc
合流部・分流部の分析、衝突速度推測、および事故予測モデルの開発：エチオピア・アディスアベバ＝アダマ有料高速道路の事例研究
Get PDF横浜国立大学博士（工学）Doctor of Philosophy in Engineerin
Research on vibration characteristics of air-supported membrane formwork during construction
Get PDF横浜国立大学博士（工学
Development and application of spray repair method and proposal of maintenance system for urban railway tunnels in salt-affected environment
Get PDF横浜国立大学博士（工学
Design guidelines of highly concentrated electrolytes and localized highconcentration electrolytes for high-performance lithium metal batteries
Get PDF横浜国立大学博士（工学）この学位論文の全文は、中央図書館で平日17時までに申請することで閲覧が可能です。The full text of this thesis is available for viewing at the Central Library upon request by 5:00 p.m. on weekdays