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1.
Mariko Hayashi Masaki Wakagawa Takafumi Minato Yuji Nishiyama Shigeki Kuroki Mitsuru Satoh 《Journal of Polymer Science.Polymer Physics》2009,47(21):2122-2131
Counterion mixing effects on the volume phase transition and the coil‐globule transition of alkali metal poly(acrylate)s (PAAM) in aqueous organic solvents were investigated by observing the swelling behavior of PAAM gel and by measuring the solution viscosity and the conductivity as a function of the counterion mixing ratio. Marked transitions to the collapsed states were induced only for Li+/Cs+ system in most solvent systems; namely, PAA gel significantly collapsed in the presence of Li+ and Cs+ counterions irrespective of the solvent species employed, while only a slight deswelling was observed for Li+/K+ system in some aqueous organic solvents. Corresponding specific decrements in the solution viscosity and conductivity were also confirmed for the combination of Li+ and Cs+ in aqueous dimethyl sulfoxide (DMSO) system. A simple analysis of the conductivity decrement observed for Li+/Cs+ system in 60 vol % DMSO suggested that only Cs+ is tightly bound upon addition of Li+ while no restriction is induced for Li+ upon mixing with Cs+. A working hypothesis is proposed for the apparently intriguing behaviors of the counterions in the mixed system. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2122–2131, 2009 相似文献
2.
Effect of 1,10-phenanthroline on the extraction and separation of lithium(I), sodium(I) and potassium(I) with thenoyltrifluoroacetone 总被引:1,自引:0,他引:1
The extraction of Li+ with thenoyltrifluoroacetone (Htta) in the presence of 1,10-phenanthroline (phen) has been studied in various organic solvents. The remarkable enhancement of the extraction of Li+, that is a synergistic effect, was observed by the addition of phen, and the high extractability of Li+ was attained in toluene, benzene, chlorobenzene and o-dichlorobenzene. The extraction equilibrium of Li+, Na+ and K+ (denoted as M+) in the presence or absence of phen in chlorobenzene and the adduct formation reaction in the organic phase were studied in detail. The adduct of Li+ was Li(tta)(phen) in the wide concentration range of phen in the organic phase, while in Na+ and K+ M(tta)(phen)2 also exists in the high concentration region. The maximum value of the separation factor between Li+ and Na+ was observed in the present system and was larger than that in the Htta-trioctylphosphine oxide (TOPO)-benzene system reported previously. 相似文献
3.
An experimental device for the calorimetric measurement of enthalpies of cation-exchange is described, giving the values of these enthalpies for K+/H+, Na+/H+, H+/Li+,K+/Li-,Na+/Li+ and K+/Na+ exchange systems on Dowex 50W with several degrees of cross-linking. Weak thermal effects of long duration have been found in these exchange processes. The influence of the exchange system and cross-linking of the resin is studied. 相似文献
4.
Integral scattering cross sections have been measured for alkali ions (Li+, Na+ and K+) in the energy range 500–4000 eV scattered by room temperature N2 and CO molecules through effective laboratory angles greater than 5 × 10?3 rad. The repulsive potentials deduced from the cross sections are represented bya practically identical formula for the Na+N2 and Na+CO systems, and for the K+CO systems, respectively, while the repulsive potentials of the Li+N2 system are somewhat smaller than those of the Li+CO system at larger intermolecular distances. 相似文献
5.
Andrzej Lasia 《Journal of Electroanalytical Chemistry》1979,102(1):117-126
The properties of the ion associates of benzophenone (BP) free radicals with Na+ and Li+ have been investigated polarographically in dimethylformamide. It was found that BP? forms ion pairs with Na+ (Kass=69 M?1) and two types of associates with Li+: BP?...Li+ (Kass,1=330 M?1) and BP?...(Li+)2(Kass,2M?2). The influence of temperature on the equilibria was also discussed. The ion associates with Li+ disappear in a disproportionation reaction; the mechanism and kinetics of that reaction were studied. It was found that the main contribution to the overall kinetics are made by the pairs (a) BP?...Li++BP?...Li+, (b) BP?+BP?...(Li+)2 (c) BP?...Li++BP?...(Li+)2. 相似文献
6.
Dr. Tingyan Ye Hongfei Gao Qi Li Prof. Nannan Liu Prof. Xueli Liu Prof. Lei Jiang Prof. Jun Gao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(7):e202316161
Biological ion channels use the synergistic effects of various strategies to realize highly selective ion sieving. For example, potassium channels use functional groups and angstrom-sized pores to discriminate rival ions and enrich target ions. Inspired by this, we constructed a layered crystal pillared by crown ether that incorporates these strategies to realize high Li+ selectivity. The pillared channels and crown ether have an angstrom-scale size. The crown ether specifically allows the low-barrier transport of Li+. The channels attract and enrich Li+ ions by up to orders of magnitude. As a result, our material sieves Li+ out of various common ions such as Na+, K+, Ca2+, Mg2+ and Al3+. Moreover, by spontaneously enriching Li+ ions, it realizes an effective Li+/Na+ selectivity of 1422 in artificial seawater where the Li+ concentration is merely 25 μM. We expect this work to spark technologies for the extraction of lithium and other dilute metal ions. 相似文献
7.
Li Jiang Prof. Yanhong Lyu Prof. Aibin Huang Prof. Jianyun Zheng Dr. Chao Xie Prof. Xun Cao Prof. Shuangyin Wang 《Angewandte Chemie (International ed. in English)》2023,62(24):e202304079
Photoelectrochemical lithium (Li) extraction can be expected to provide a useful recycle of Li+ from waste Li-containing battery, but the process is limited by the photocathodes with poor Li+ absorption and low yield rate. Here, we have designed a hierarchical silicon (Si)-based photocathode with mixed-phase tungsten oxide (WO3) cocatalysts for photoelectrochemical Li extraction under 1 sun illumination, achieving a high Li yield rate of ≈223.0 μg cm−2 h−1 and an excellent faradaic efficiency of 91.9 % at 0.0817 V versus Li0/+ redox couple. The WO3 cocatalysts with the mixture of amorphous and crystalline phase accelerates the Li+ insertion and precipitation and enriches the concentration of Li+ at the photocathode surface. This robust photoelectrochemical Li extraction system provides a new insight on designing green and efficient route for cyclic utilization of Li resources in the sustainable energy field. 相似文献
8.
Hongbo Qian Shaodong Huang Zhichen Ba Wenxuan Wang Feihan Yu Daxin Liang Yanjun Xie Yonggui Wang Yan Wang 《Molecules (Basel, Switzerland)》2021,26(13)
To achieve rapid and highly efficient recovery of Li+ from seawater, a series of H2TiO3/cellulose aerogels (HTO/CA) with a porous network were prepared by a simple and effective method. The as-prepared HTO/CA were characterized and their Li+ adsorption performance was evaluated. The obtained results revealed that the maximum capacity of HTO/CA to adsorb Li+ was 28.58 ± 0.71 mg g−1. The dynamic k2 value indicated that the Li+ adsorption rate of HTO/CA was nearly five times that of HTO powder. Furthermore, the aerogel retained extremely high Li+ selectivity compared with Mg2+, Ca2+, K+, and Na+. After regeneration for five cycles, the HTO/CA retained a Li+ adsorption capacity of 22.95 mg g−1. Moreover, the HTO/CA showed an excellent adsorption efficiency of 69.93% ± 0.04% and high selectivity to Li+ in actual seawater. These findings confirm its potential as an adsorbent for recovering Li+ from seawater. 相似文献
9.
Jesús Antonio Luque-Urrutia Dr. Albert Poater Prof. Dr. Miquel Solà 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(4):804-808
From the analysis of the polarizability of carbon nano-onions (CNOs), it was concluded that CNOs behave as near perfect nanoscopic Faraday cages. If CNOs behave as ideal Faraday cages, the reactivity of the C240 cage should be the same in Li+@C240 and Li+@C60@C240. In this work, the Diels–Alder reaction of cyclopentadiene to the free C240 cage and the C60@C240 CNO together with their Li+-doped counterparts were analyzed using DFT. It was found that in all cases the preferred cycloaddition is on bond [6,6] of type B of C240. Encapsulation of Li+ results in lower enthalpy barriers due to the decrease of the energy of the LUMO orbital of the C240 cage. When the Li+ is placed inside the CNO C60@C240, the decrease in enthalpy barrier is similar to that of Li+@C240. However, the location of Li+ in Li+@C240 (off-centered) and Li+@C60@C240 (centered) is quite different. When Li+ was placed in the center of the C240 cage in Li+@C240, the barriers increased significantly. Taking into account this effect, the barriers in Li+@C240 and Li+@C60@C240 differ by about 4 kcal mol−1. This result can be attributed to the shielding effect of C60 in Li+@C60@C240. As a result, we conclude that this CNO does not act as a perfect Faraday cage. 相似文献
10.
Experimental Signature of Microheterogeneity in Ionic Liquid–H2O Systems and Their Perturbation by Adding Li+ Salts: A Pulsed Gradient Spin‐Echo NMR Approach
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Distinct microheterogeneity has been observed in the [OMIM]Br–H2O system, which is interestingly perturbed by the addition of Li+ salts, indicating unusual diffusivity of [OMIM]Br and H2O molecules. However, the diffusional dynamics of water clusters show contrasting salting behavior at higher concentrations of Li+ salts, following the classical salting phenomenon in lower amounts. In contrast, the existing microheterogeneity in the [BMIM]Br–H2O system is weak enough to show any perturbation caused by the Li+ salts on the NMR time scale. 相似文献
11.
Manuel Alcamí Otilia Mó José Juis G. de Paz Manuel Yáñez 《Theoretical chemistry accounts》1990,77(1):1-15
Summary Hartree-Fock calculations with the 6–31G* basis have been performed to investigate the structure and Li+ binding energies of the complexes between Li+ and pyridine, diazines, triazines and tetrazines. Structures have been fully optimized at the 3–21G level. As for azole-Li+ and methyldiazole-Li+ complexes, a topological analysis of the Laplacian of the electronic charge density reveals that the azine-Li+ is a typical closed-shell interaction and that the stabilization of the complex is mainly electrostatic. BSSE is quite significant, specially for Li+-bridging complexes. The correlation between calculated Li+ binding energies and proton affinities follows two different linear relationships, one for those cases where Li+ is singly coordinated and a different one for those cases in which an additional three-membered ring is formed. The enhanced stability of these particular conformations explains why while polyazines are less basic than pyridine when the reference acid is a proton; pyridazine and 1,2,4 triazine are more basic than pyridine when the reference acid is Li+. The effect on Li+ binding energies of systematic nitrogen substitution roughly follows an additive model. 相似文献
12.
A new model for the diffuse double layer which accounts for the effects of ion size and solution permittivity is described. It is then used to estimate the potential drop across the diffuse layer at negative charge densities for the cases that Li+ and Cs+ are the electrolyte cations. The potential drop in the Li+ system is considerably smaller than that in the Cs+ system at 1 M, and both values are smaller than the value predicted by the Gouy–Chapman model. As the electrolyte concentration decreases these differences become smaller so that at 0.01 M, the present model predicts that the diffuse layer potential drop is approximately 90% of the Gouy–Chapman estimate. The results of the model are used to examine the differences in inner layer structure at mercury electrodes with Li+ and Cs+ ions at the outer Helmholtz plane, and to reconsider the question of the specific adsorption of Cs+ at negative-charge densities. 相似文献
13.
V. P. Tysyachnyi R. D. Apostolova E. M. Shembel’ 《Russian Journal of Electrochemistry》2009,45(5):554-557
A comparison was made for Li+ chemical diffusion coefficients (D Li) in graphite as calculated by mathematical models of Li+ intercalation under constant potential into semirestricted and restricted kinetic systems with mobile phase boundary and into a single-phase system. Close D Li values were calculated by means of double-phase models. The double-phase model produces 6–7-fold D Li coefficient as compared to the values of the single-phase model. 相似文献
14.
Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C60 to Afford Efficient Photodriven Charge Separation
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Dr. Mustafa Supur Yuki Kawashima Dr. Karina R. Larsen Dr. Kei Ohkubo Prof. Jan O. Jeppesen Prof. Shunichi Fukuzumi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):13976-13983
Inclusion complexes of benzo‐ and dithiabenzo‐crown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C60 ( 1? Li+@C60 and 2? Li+@C60). The strong complexation has been quantified by high binding constants that exceed 106 M ?1 obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6‐311G(d,p) level, the orbital interactions between the crown ether moieties and the π surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation. Interestingly, complexation of Li+@C60 with crown ethers accelerates the intersystem crossing upon photoexcitation of the complex, thereby yielding 3(Li+@C60)*, when no charge separation by means of 1Li+@C60* occurs. Photoinduced charge separation by means of 3Li+@C60* with lifetimes of 135 and 120 μs for 1? Li+@C60 and 2? Li+@C60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time‐resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures affects the binding constant and the rates of photoinduced electron‐transfer events in the corresponding complex. 相似文献
15.
Kean Chen Xiaohui Shen Laibing Luo Hui Chen Ruoyu Cao Prof. Xiangming Feng Prof. Weihua Chen Prof. Yongjin Fang Prof. Yuliang Cao 《Angewandte Chemie (International ed. in English)》2023,62(47):e202312373
The solvation structure of Li+ plays a significant role in determining the physicochemical properties of electrolytes. However, to date, there is still no clear definition of the solvating power of different electrolyte solvents, and even the solvents that preferentially participate in the solvation structure remain controversial. In this study, we comprehensively discuss the solvating power and solvation process of Li+ ions using both experimental characterizations and theoretical calculations. Our findings reveal that the solvating power is dependent on the strength of the Li+-solvent (ion-dipole) interaction. Additionally, we uncover that the anions tend to enter the solvation sheath in most electrolyte systems through Li+-anion (ion-ion) interaction, which is weakened by the shielding effect of solvents. The competition between the Li+-solvent and Li+-anion interactions ultimately determines the final solvation structures. This insight into the fundamental understanding of the solvation structure of Li+ provides inspiration for the design of multifunctional mixed-solvent electrolytes for advanced batteries. 相似文献
16.
Polystyrene Sulfonate Threaded through a Metal–Organic Framework Membrane for Fast and Selective Lithium‐Ion Separation
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Dr. Yi Guo Dr. Yulong Ying Dr. Yiyin Mao Prof. Xinsheng Peng Prof. Banglin Chen 《Angewandte Chemie (International ed. in English)》2016,55(48):15120-15124
Extraction of lithium ions from salt‐lake brines is very important to produce lithium compounds. Herein, we report a new approach to construct polystyrene sulfonate (PSS) threaded HKUST‐1 metal–organic framework (MOF) membranes through an in situ confinement conversion process. The resulting membrane PSS@HKUST‐1‐6.7, with unique anchored three‐dimensional sulfonate networks, shows a very high Li+ conductivity of 5.53×10?4 S cm?1 at 25 °C, 1.89×10?3 S cm?1 at 70 °C, and Li+ flux of 6.75 mol m?2 h?1, which are five orders higher than that of the pristine HKUST‐1 membrane. Attributed to the different size sieving effects and the affinity differences of the Li+, Na+, K+, and Mg2+ ions to the sulfonate groups, the PSS@HKUST‐1‐6.7 membrane exhibits ideal selectivities of 78, 99, and 10296 for Li+/Na+, Li+/K+, Li+/Mg2+ and real binary ion selectivities of 35, 67, and 1815, respectively, the highest ever reported among ionic conductors and Li+ extraction membranes. 相似文献
17.
Ab initio wavefunctions have been calculated for the complex of Li+ with NH3 and H2O in order to better characterize the nature of the bonding. Hartree—Fock and generalized valence bond calculations were performed using a double zeta basis plus polarization functions. The binding energies obtained at the GVB level are De (Li+ — NH3) = 40.4 kcal/mol and De (Li+ ? H2O) = 37.6 kcal/mol, in reasonable agreement with experimental values. Model calculations indicate that the Li+ ? base bond is basically electrostatic. Small basis sets were found to lead to De as large as 75 kcal/mol for Li+ — NH3, a significant overestimation. Repulsions due to the Li+ core are responsible for keeping the Li+ too far away for significant relaxation effects. 相似文献
18.
Determination of Stability Constants in Ethanol for Li+-selective Ionophores by Differential Vapour Pressure Osmometry Stability constants of some neutral carriers and their bridged isologues in interaction with Li+ and Na+ are determined by a differential vapour pressure osmometry method in ethanol utilizing Bjerrum formation curves. All ionophores studied induce high Li+ selectivity in solvent polymeric membranes. 相似文献
19.
Mahdiyeh Bamdad Hossein Farrokhpour Bijan Najafi Mahmud Ashrafizaadeh 《Structural chemistry》2018,29(6):1745-1751
In this work, the interaction of three Li+-doped polycyclic hydrocarbons (Li+-DPH) with H2 and H2O was calculated to investigate the effect of curvature of substrate on the interaction energy (Eint). For this purpose, the Eint and its decomposed energy components (electrostatic (Eelec), exchange (Eexch), induction (Eind), and dispersion energy (Edisp)) were calculated using DF-SAPT (DFT) methodology for the selected systems (Li+-(3,3) carbon nanotube (Li+-CNT33), Li+-(6,6) carbon nanotube (Li+-CNT66), and Li+-graphene). According to the results, Eint does not change significantly with curvature for the interaction between both H2 and H2O gases and the selected Li+-DPH. Since the variation of the Eint with the curvature of Li+-DPH is not significant, the selection of a planar Li+-DPH is a trustworthy model to develop a general force field for describing the interaction between a Li+-DPH and adsorbed gases. The results reveal that, in the case of the H2, the components Eelect, Eexch, Eind, and Edisp have shown a decreasing trend with Li+-DPH’s curvature decrement. However, for the H2O, Eelect, Eexch, and Eind decrease from the Li+-CNT33 to the Li+-CNT66 while they increase from the Li+-CNT66 to the Li+-graphene. In this case, the Edisp increases with a decrease of the curvature of Li+-DPH. Finally, it can be seen that although the variation of the Eint with the curvature of Li+-DPH is not significant, the variation trend of the interaction energy components and the amount of variation depend on the gas molecule and in some cases are not negligible. 相似文献
20.
Nan Wu Po‐Hsiu Chien Yumin Qian Yutao Li Henghui Xu Nicholas S. Grundish Biyi Xu Haibo Jin Yan‐Yan Hu Guihua Yu John B. Goodenough 《Angewandte Chemie (International ed. in English)》2020,59(10):4131-4137
Li+‐conducting oxides are considered better ceramic fillers than Li+‐insulating oxides for improving Li+ conductivity in composite polymer electrolytes owing to their ability to conduct Li+ through the ceramic oxide as well as across the oxide/polymer interface. Here we use two Li+‐insulating oxides (fluorite Gd0.1Ce0.9O1.95 and perovskite La0.8Sr0.2Ga0.8Mg0.2O2.55) with a high concentration of oxygen vacancies to demonstrate two oxide/poly(ethylene oxide) (PEO)‐based polymer composite electrolytes, each with a Li+ conductivity above 10?4 S cm?1 at 30 °C. Li solid‐state NMR results show an increase in Li+ ions (>10 %) occupying the more mobile A2 environment in the composite electrolytes. This increase in A2‐site occupancy originates from the strong interaction between the O2? of Li‐salt anion and the surface oxygen vacancies of each oxide and contributes to the more facile Li+ transport. All‐solid‐state Li‐metal cells with these composite electrolytes demonstrate a small interfacial resistance with good cycling performance at 35 °C. 相似文献