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Chitosan has been successfully incorporated as a filler in a polyethylene oxide (PEO) and lithium trifluoromethanesulfonate (LiCF3SO3) matrix with a combination of plasticizers, namely 1,3-dioxolane (DIOX) and tetraethylene glycol dimethylether (TEGDME). The composite gel-polymer electrolyte (CGPE) membranes were prepared by solution casting technique in an argon atmosphere. The prepared membranes were subjected to SEM, TG/DTA and FT-IR analyses. A Li/CGPE/Li symmetric cell was assembled and the variation of interfacial resistance was measured as a function of time. The lithium transference number (Li+t) was measured and the value was calculated as 0.6 which is sufficient for battery applications. The electrochemical stability window of the sample was studied by linear sweep voltammetry and the polymer electrolyte was found to be stable up to 5.2 V.

Membrane resistance and permselectivity for counter-ions have important roles in determining the performance of cation-exchange membranes (CEMs). In this study, PVA-based polyanions—poly(vinyl alcohol-b-sodium styrene sulfonate)—were synthesized, changing the molar percentages CCEG of the cation-exchange groups with respect to the vinyl alcohol groups. From the block copolymer, poly(vinyl alcohol) (PVA)-based CEMs, hereafter called “B-CEMs”, were prepared by crosslinking the PVA chains with glutaraldehyde (GA) solution at various GA concentrations CGA. The ionic transport properties of the B-CEMs were compared with those previously reported for the CEMs prepared using a random copolymer—poly(vinyl alcohol-co-2-acrylamido-2-methylpropane sulfonic acid)—hereafter called ”R-CEMs”. The B-CEMs had lower water content than the R-CEMs at equal molar percentages of the cation-exchange groups. The charge density of the B-CEMs increased as CCEG increased, and reached a maximum value, which increased with increasing CGA. A maximum charge density of 1.47 mol/dm3 was obtained for a B-CEM with CCEG = 2.9 mol% and CGA = 0.10 vol.%, indicating that the B-CEM had almost two-thirds of the permselectivity of a commercial CEM (CMX: ASTOM Corp. Japan). The dynamic transport number and membrane resistance of a B-CEM with CCEG = 8.3 mol% and CGA = 0.10 vol.% were 0.99 and 1.6 Ωcm2, respectively. The B-CEM showed higher dynamic transport numbers than those of the R-CEMs with similar membrane resistances.

We report a thorough, multitechnique investigation of the structure and transport properties of a UV-cross-linked polymer electrolyte based on poly(ethylene oxide), tetra(ethylene glycol)dimethyl ether (G4), and lithium bis-(trifluoromethane)sulfonimide. The properties of the cross linked polymer electrolyte are compared to those of a non cross-linked sample of same composition. The effect of UV induced cross-linking on the physico/chemical characteristics is evaluated by X-ray diffraction, differential scanning calorimetry, shear rheology, and Li-7 magic angle spinning nuclear magnetic resonance (NMR) spectroscopy, F-19 and Li-7 pulsed field gradient stimulated echo NMR analyses, electrochemical impedance spectroscopy, and Fourier transform Raman spectroscopy. Comprehensive analysis confirms that UV-induced cross-linking is an effective technique to suppress the crystallinity of the polymer matrix and reduce ion aggregation, yielding improved Li+ transport number (>0.5) and ionic conductivity (>0.1 mS cm(-1)) at ambient temperature, by tailoring the structural/morphological characteristics of the polymer matrix. Finally, the polymer electrolyte allows reversible operation with stable profile for hundreds of cycles upon galvanostatic test at ambient temperature of LiFePO4-based lithium-metal cells, which deliver full capacity at 0.05 or 0.1C current rate and keep high rate capabilities up to 1C. This enforces the role of UV-induced cross-linking in achieving excellent electrochemical characteristics, exploiting a practical, easy up-scalable process.

Sesium klorida adalah senyawa anorganik dengan rumus CsCl. Senyawa ini dapat dengan mudah larut dalam air. Sesium klorida memiliki toksisitas rendah terhadap manusia dan hewan, sedangkan bentuk radioaktif dari senyawa ini dapat dengan mudah mencemari lingkungan karena kelarutan airnya. Senyawa ini digunakan dalam proses sentrifugasi isopicnik dalam pemisahan berbagai jenis DNA dan juga digunakan untuk analisis reagen kimia. Dalam bentuk isotop radio, senyawa ini berguna untuk pengobatan nuklir, yaitu untuk pengobatan kanker. Penelitian ini bertujuan untuk menganalisis interaksi molekuler dan kinetik dari senyawa sesium klorida. Metode yang digunakan adalah dengan pemodelan menggunakan chemoffice serta melalui jurnal hasil penelitian yang berkaitan dengan sesium klorida. Sifat sifat trermokimia dari senyawa sesium klorida dalam fase liquid ∆Ho : -434.47 KJ/mol, so : 101.71 J/molK dan ∆Go : -414.5 KJ/mol. Data ini di peroleh dari wikipedia. Parameter transfer elektron adalah kecepatan drift, nomor angkut, mobilitas ion, difusi dan hukum I Fick.

The transport of As (V) oxianions was modeled through the boundary layer generated between the bulk of an acidic As (V) electrolyte and the surface of an anionic exchange membrane during a batch electro dialysis process without agitation. The model was adapted from one developed for the transport of Cu (II) ions in the Nernst layer under the same hydrodynamic and electric conditions. The model shows the flux of oxianions in terms of the difference between the transport number of As (V) in the boundary layer and in the membrane as a function of the current density. The model approaches to the experimental data when the transport number in the boundary layer is 1.5x10-4 and 1.5x10-5 for As (V)-H2SO4 and As (V)-Cu (II)-H2SO4 electrolytes, respectively. The validation of the model was made with published data of As (V) transport.Se describe el transporte de oxianiones de As (V) a través de la capa límite generada entre el seno de un electrólito ácido de As (V) y la superficie de una membrana de intercambio aniónico durante un proceso discontinuo de electro diálisis sin agitación, para lo cual se adaptó un modelo desarrollado para describir el transporte catiónico de Cu (II) en la capa de Nernst bajo las mismas condiciones hidrodinámicas y de potencial eléctrico. El flujo de oxianiones se describe en términos de la diferencia entre el número de transporte de los oxianiones de As (V) en la capa límite (modelado) y en la membrana en función de la densidad de corriente aplicada. El modelo converge a los datos experimentales cuando el número de transporte en la capa límite es de 1,5X10-4 y 1,5X10-5 para electrólitos de As (V)-H2SO4 y As (V)-Cu (II)-H2SO4, respectivamente. La validación del modelo se realizó con datos publicados de transporte de As (V).

Poly(vinylidene fluoride-hexafluropropylene) (PVDF-HFP) and poly(methyl methacrylate) (PMMA)-based gel polymer electrolytes (GPEs) comprising propylene carbonate and diethyl carbonate mixed plasticizer with variation of lithium perchlorate (LiClO4) salt concentrations have been prepared using a solvent casting technique. Structural characterization has been carried out using XRD wherein diffraction pattern reveals the amorphous nature of sample up to 7.5[Formula: see text]wt.% salt and complexation of polymers and salt have been studied by FTIR analysis. Surface morphology of the samples has been studied using scanning electron microscope. Electrochemical impedance spectroscopy in the temperature range 303–363[Formula: see text]K has been carried out for electrical conductivity. The maximum room temperature conductivity of 2.83[Formula: see text][Formula: see text]S cm[Formula: see text] has been observed for the GPE incorporating 7.5[Formula: see text]wt.% LiClO4. The temperature dependence of ionic conductivity obeys the Arrhenius relation. The increase in ionic conductivity with change in temperatures and salt content is observed. Transport number measurement is carried out by Wagner’s DC polarization method. Loss tangent (tan [Formula: see text]) and imaginary part of modulus ([Formula: see text]) corresponding to dielectric relaxation and conductivity relaxation respectively show faster relaxation process with increasing salt content up to optimum value of 7.5[Formula: see text]wt.% LiClO4. The modulus ([Formula: see text]) shows that the conductivity relaxation is of non-Debye type (broader than Debye peak).

A semi empirical model was developed to characterize the transport of cupric ions within the Nernst layer generated between electrolyte bulk and the membrane surface in an electrodialysis cell. The model was derived from fundamental equations and was reduced to a linear expression incorporating the cupric ion transport number in the Nernst layer (t+BL) and in the membrane (t+M). The model critical condition is t+BL < 0.5 t+M. The model correctly fits the experimental data when t+BL is 0.02. The model was validated with experimental results previously published by the authors and it accounts for a linear concentration gradient within the Nernst layer.Se ha desarrollado un modelo semi empírico que permite establecer el transporte de iones cúpricos a través de la capa límite de Nernst generada entre el seno del electrólito y la superficie de la membrana de una celda de electrodiálisis. El modelo, desarrollado a partir de ecuaciones fundamentales de flujo iónico, fue reducido a una expresión lineal que incorpora los números de transporte en la capa de Nernst (t+BL) y en la membrana (t+M). La condición crítica del modelo es que t+BL < 0,5 t+M. El modelo desarrollado converge a los datos experimentales cuando t+BL toma el valor de 0,02. El modelo propuesto fue validado con datos experimentales publicados previamente por los autores y da cuenta de la existencia de un gradiente de concentración lineal de cobre en la capa límite.

International audience; The ionic behavior of an aromatic lithium sulfonyl imide, i.e. lithium bis(4nitrophenyl)sulfonylimide, has been investigated in an amorphous poly(oxyethylene) network and compared to that of usual lithium salts dissolved in the same host polymer. The NO2 groups which are substituents at both phenyl groups, are expected to induce a strong electron-withdrawing effect on the imide negative charge to provide large delocalization and therefore generate high charge carrier concentration. The conductivities observed are lower than those of lithium salts such as (CF3SO2)2NLi (LiTFSI) dissolved in the same host polymer. An important increase of Tg with salt concentration reflects a greater stiffness of the polymer induced by the aromatic rings, which reduces mobility, and might account for the lower conductivity. Interestingly, the aromatic imide exhibits higher cationic mobility with t+ ranging between 0.4 and 0.45, compared to 0.08–0.12 for the fluorinated imide. Cyclic voltammetry shows that lithium bis(4-nitrophenyl)sulfonylimide undergoes irreversible reduction before lithium plating, which has been attributed to the presence of nitro group.

The transport of As (V) oxianions was modeled through the boundary layer generated between the bulk of an acidic As (V) electrolyte and the surface of an anionic exchange membrane during a batch electro dialysis process without agitation. The model was adapted from one developed for the transport of Cu (II) ions in the Nernst layer under the same hydrodynamic and electric conditions. The model shows the flux of oxianions in terms of the difference between the transport number of As (V) in the boundary layer and in the membrane as a function of the current density. The model approaches to the experimental data when the transport number in the boundary layer is 1.5x10-4 and 1.5x10-5 for As (V)-H2SO4 and As (V)-Cu (II)-H2SO4 electrolytes, respectively. The validation of the model was made with published data of As (V) transport. Se describe el transporte de oxianiones de As (V) a través de la capa límite generada entre el seno de un electrólito ácido de As (V) y la superficie de una membrana de intercambio aniónico durante un proceso discontinuo de electro diálisis sin agitación, para lo cual se adaptó un modelo desarrollado para describir el transporte catiónico de Cu (II) en la capa de Nernst bajo las mismas condiciones hidrodinámicas y de potencial eléctrico. El flujo de oxianiones se describe en términos de la diferencia entre el número de transporte de los oxianiones de As (V) en la capa límite (modelado) y en la membrana en función de la densidad de corriente aplicada. El modelo converge a los datos experimentales cuando el número de transporte en la capa límite es de 1,5X10-4 y 1,5X10-5 para electrólitos de As (V)-H2SO4 y As (V)-Cu (II)-H2SO4, respectivamente. La validación del modelo se realizó con datos publicados de transporte de As (V).

Effects of ion species and their concentration on the iontophoretic transport of benzoic acid through an artificial membrane [poly(vinyl acetate)] were investigated using a 2-chamber diffusion cell equipped with platinum electorodes and a constant current power source. The cathode side of the cell was filled with sodium benzoate solution, and the anode side with pottassium chloride, lithium chloride or teraethylammonium bromide solution. When the molar concentration of sodium benzoate in the cathode side (0.21 M) was the same as the potassium chloride in the anode side, the amounts of benzoate anion and potassium cation permeated through the membrane were greater with increasing current. With an increase in the concentration of benzoate anion in the cathode side and a constant concentration of potassium cation in the anode side, the amount of the former that permeated was proportional to the concentration applied, while permeation of potassium cation remained almost constant at a constant current of 0.2mA. Conversely, an increase in the concentration of potassium cation in the anode side with a constant concentration of benzoate anion in the cathode side resulted in an increase of the permeation of potassium cation and a decrease of that of benzoate anion, respectively, at the same constant current. When potassium chloride in the anode side was replaced by tetraethylammonium bromide, the amount of benzoate anion permeated was increased at a constant current of 0.2mA. These results may be explained by the following theory on the transport number of each ion through the artificial membrane : Current density calculated from ion flux throutgh the membrane was almost the same as that measured by observed current density. The results appeared to indicate that not only an ion species and its concentration in the donor solution but also ion species in the receiver solution should be considered when evaluating the iontophoretic transport phenomena.

A semi empirical model was developed to characterize the transport of cupric ions within the Nernst layer generated between electrolyte bulk and the membrane surface in an electrodialysis cell. The model was derived from fundamental equations and was reduced to a linear expression incorporating the cupric ion transport number in the Nernst layer (t+BL) and in the membrane (t+M). The model critical condition is t+BL < 0.5 t+M. The model correctly fits the experimental data when t+BL is 0.02. The model was validated with experimental results previously published by the authors and it accounts for a linear concentration gradient within the Nernst layer. Se ha desarrollado un modelo semi empírico que permite establecer el transporte de iones cúpricos a través de la capa límite de Nernst generada entre el seno del electrólito y la superficie de la membrana de una celda de electrodiálisis. El modelo, desarrollado a partir de ecuaciones fundamentales de flujo iónico, fue reducido a una expresión lineal que incorpora los números de transporte en la capa de Nernst (t+BL) y en la membrana (t+M). La condición crítica del modelo es que t+BL < 0,5 t+M. El modelo desarrollado converge a los datos experimentales cuando t+BL toma el valor de 0,02. El modelo propuesto fue validado con datos experimentales publicados previamente por los autores y da cuenta de la existencia de un gradiente de concentración lineal de cobre en la capa límite.

Effect of species and concentrations of pharmaceutical additives on the iontophoretic transport of benzoate anion through excised hairless rat skin was investigated using a 2-chamber iontophoretic diffusion cell quipped with platinum electrodes at 0 mA for 4 h (control) followed by a constant direct current of 0.5 mA for another 4 h. One cell facing the stratum corneum was filled with sodium benzoate solution, and the other cell facing the dermis with lithium chloride (LiCl), potassium chloride (KCl) or tetraethylammonium bromide (TEA-Br) solution. Iontophoretic delivery rate of benzoate anion that permeated through skin increased with an increase in the sodium benzoate concentration while maintaining a constant KCl concentration. In contrast, a flux of benzoate anion decreased with an increase in KCl concentration and a constant concentration of sodium benzoate. When KCl was replaced by LiCl or TEA-Br, the flux of benzoate anion was almost the same. These phenomena were evaluated by a concept of transport numbers : theoretical values of benzoate anion flux were very close to the observed data. Potential difference between the skin during the permeation study was also measured between two salt bridges which were connected via calomel electrodes to a potentiometer. It gradually decreased to a certain level in each case, but increased again in some cases. This gradual decrease and increase in the potential difference, in spite of a constant current, were theoretically explaind by a gradual increase of ion concentration in the skin membrane and depletion of the cation in the receiver cell, respectively. Analysis of ionic mobility and concentration of penetrants gave a great deal of information on iontophoretic drug permeation through skin.

A combination of impedance spectroscopy and a modified electromotive force method (emf) were used to evaluate the ionic transport numbers and the overall conductivity of several doped lanthanum gallate materials, i.e. La0.9Sr0.1Ga1-xMgxO3-δ (x=0.05-0.30), La0.9A0.1Ga0.8Mg0.2O3-δ (A=Sr, Ba and Ca) and La0.9Sr0.1Ga0.8Mg0.2-yCoyO3-δ (y=0.015 and 0.045). La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) sample showed the maximum ionic transport number in the temperature range 900-1173 K, around 0.99 in both O2/air and H2/air gradients.La conductividad total y los números de transporte iónico de las composiciones, basadas en el galato de lantano, La0,9Sr0,1Ga1-xMgxO3-δ (x=0,05-0,30), La0,9A0,1Ga0,8Mg0,2O3-δ (A=Sr, Ba, Ca) y La0,9Sr0,1Ga0,8Mg0,2-yCoyO3-δ (y=0.015; 0,045) fueron estudiadas mediante una combinación de técnicas de espectroscopia de impedancia compleja y fuerza electromotriz (fem). La composición La0,9Sr0,1Ga0,8Mg0,2O2,85 (LSGM) presenta el mayor número de transporte iónico, concretamente 0,99 en el rango de temperaturas 900-1173 K, tanto en gradiente de O2/aire como de H2/aire.

The transport properties of various anion and cation exchange membranes were studied in different electrolyte solutions using chronopotentiometry technique to get insight about the influence of the counter ion on the transport properties of the membranes. The investigated samples include heterogeneous ion exchange membranes varying in the functionality of fixed charged groups, physical properties of the polymer and the preparation procedure. Chloride and nitrate were investigated as counter-ion in their sodium salts for anion exchange membranes while sodium, calcium, potassium, and magnesium were selected as counter-ion in their chloride salts to study cation exchange membranes transport properties. First, the current – voltage curve of an ion exchange membrane in a given solution was recorded to obtain the limiting current, then a constant current above the limiting current was used for chronopotentiometry measurement. In all the studied membranes the potential across the membrane remained constant for a time interval called the transition time , when a constant current was applied. Then the potential increased rapidly to reach the steady state potential. The permselectivty and the transport number of a membrane were calculated using the corresponding transition time.