Sulfolane electrolytes

QCMB RAM SBR SEI SEM SERS SFL SHE SLI SNIFTIRS quartz crystal microbalance rechargeable alkaline manganese dioxide-zinc styrene-butadiene rubber solid electrolyte interphase scanning electron microscopy surface enhanced Raman spectroscopy sulfolane-based electrolyte standard hydrogen electrode starter-light-ignition subtractively normalized interfacial Fourier transform infrared... 

The supporting electrolytes were 0.1 M [n-Bu NlClO for CH3CN, EtOH, CH2C12, EtOH/toluene (1 1 v/v). sulfolane, and glacial acetic acid solvents, and 1.0 M NaClO /0.01-0.1 M HCIO for H2O, E. values for I oxidation were obtained at Pt... 

However, for certain applications non-aqueous solvents have their advantages. Uni-univalent electrolytes dissolved at low to moderate concentrations in solvents with a relative permittivity larger than, approximately, 30 are completely dissociated into ions. Of the solvents on the List, methanol, glycols, glycerol, formic acid, ethylene and propylene carbonate, 4-butyrolactone, ethanolamine, 2-cyanopyridine, acetonitrile, nitromethane and -benzene, the amides, whether N-substituted or not, dimethyl sulfoxide, sulfolane, dimethyl sulfate, and hexamethyl phosphoramide have s > 30 at ambient conditions (Table 3.5). Most of these solvents have, indeed, been used in electrochemical processes. 

The solvents used for electroanalytical determinations vary widely in their physical properties liquid ranges (e.g., acetamide, N-methyl-acetamide and sulfolane are liquid only above ambient temperatures), vapour pressures (Table 3.1), relative permittivities (Table 3.5), viscosities (Table 3.9), and chemical properties, such as electron pair and hydrogen bond donicities (Table 4.3), dissolving ability of the required supporting electrolyte to provide adequate conductivity, and electrochemical potential windows (Table 4.8). A suitable solvent can therefore generally be found among them that fits the electroanalytical problem to be solved. 

Another solvent that has received some attention in connection with rechargeable Li batteries is sulfolane [214], The surface chemistry of lithium electrodes in 3-methyl sulfolane/LiAsF6 solutions was studied by Yen et al. [215] using XPS and FTIR. Their analysis of the surface chemistry of Li electrodes in these electrolyte systems is summarized in Scheme 7. 

Conductance and Ionic Association of Several Electrolytes in Binary Mixtures Involving Sulfolane (TMS) and Protic Solvents... 

Conductometric and spectrophotometric behavior of several electrolytes in binary mixtures of sulfolane with water, methanol, ethanol, and tert-butanol was studied. In water-sulfolane, ionic Walden products are discussed in terms of solvent structural effects and ion-solvent interactions. In these mixtures alkali chlorides and hydrochloric acid show ionic association despite the high value of dielectric constants. Association of LiCl, very high in sulfolane, decreases when methanol is added although the dielectric constant decreases. Picric acid in ethanol-sulfolane and tert-butanol-sulfolane behaves similarly. These findings were interpreted by assuming that ionic association is mainly affected by solute-solvent interactions rather than by electrostatics. Hydrochloric and picric acids in sulfolane form complex species HCl and Pi(HPi). ... 

Preferential Solvation of Some Electrolytes by Water and Diethyl Ether in Sulfolane... 

HP he study of the behavior of electrolytes in mixed solvents is currently arousing considerable interest because of its practical and fundamental implications (1). Among the simpler binary solvent mixtures, those where water is one component are obviously of primary importance. We have recently compared the effects of small quantities of water on the thermodynamic properties of selected 1 1 electrolytes in sulfolane, acetonitrile, propylene carbonate, and dimethylsulfoxide (DMSO). These four compounds belong to the dipolar aprotic (DPA) class of solvents that has received a great deal of attention (2) because of their wide use as media for physical separations and chemical and electrochemical reactions. We interpreted our vapor pressure, calorimetry, and NMR results in terms of preferential solvation of small cations and anions by water and obtained... 

Figure 1. Vapor pressure of sulfolane solutions of electrolytes as a function of water concentration at 30°C (O), sulfolane (A),...

Table I. Heats of Mixing of Water with Sulfolane Solutions of Electrolytes at 30°C...

One of the HEC cells having the composition ICS-2ME/TEOS/TEG/OxA/NH4I +12 was continuously cycled more than 5000 times. Current densities continuously dropped in the course of cycling, as shown in Fig. 3. Examination of the electrolyte after the cell was dismantled under SEM and optical microscope did not reveal crystallites as formed with other electrolytes prepared with either sulfolane or EtOH in combination with ICS-PPG4000/KI +12 and AcOH or valeric acid catalyst [7, 8, 10]. This demonstrates the advantages of the electrolyte s composition based on the combination of precursors with a network former (TEOS) and suitable co-solvents (TEG). Further studies are under way to assess the advantages of the synthesized precursors and ionic liquids for HEC cells, and the application of these redox electrolytes in the DSPEC cells is to be tested. 

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