Two classes of alkali metal single-ion conducting polymer electrolytes have been characterized and their conductivities examined. Both polymers are sodium ion conductors. The first class is based upon a tetra(alkoxy)-aluminate counterion incorporated into a polyether network, and the second has a sulfonate counterion covalently bonded to a phosphazene backbone. The temperature dependent and concentration dependent conductivities of these polymers are contrasted. Phosphazene polymers that are anion conductors are also discussed.

Alkali metal polyiodide complexes of polyethers, of the type (polymer)nMIx, [Polymer - poly(ethylene oxide), PEO; poly(propylene oxide), PPO; or poly-(bis(methoxyethoxyethoxy)phosphazene), MEEP, and M - Li or Na] have been prepared and characterized in order to elucidate the nature of the observed ionic and electronic conductivities. Raman spectra of the polyiodide complexes indicate that the relative concentrations of the polyiodide species (such as I3- and higher polyiodides) depend on the salt concentration in the polymer as well as on the iodine to cation ratio. The ionic conduction can best be described by a free volume (VTF) mechanism where both polymer motion and ion mobility are activated processes. The magnitude of the electronic and ionic conductivities are a function of polymer to salt ratio as well as iodine content.

Comb polyelectrolytes consisting of a polysiloxane backbone with tetraglyme and lithium-sulfonate terminated perfluoroether side chains have been synthesized. Both types of side chains were independently prepared with allyl functionality and attached to poly(methylhydrosiloxane) by hydrosilylation. Several methods are described to form lithium sulfonate from sulfonate esters. Spectroscopic and thermal characterizations of the resulting polyelectrolyte are described.

The ion conductivity has been studied in comb polyelectrolytes consisting of a polysiloxane backbone with oligoether and lithium-sulfonate terminating perfluoroether sidechains. The room-temperature conductivity was found to reach a maximum of 2.5 x 10(-6) S/cm at 33 etheric oxygens per lithium ion. The cation mobility is coupled to the polymer segmental motion and is described by the Vogel-Tamman-Fulcher (VTF) equation. The mechanisms behind ion mobility are studied by means of the VTF parameters sigma(0), B, and T-0. In particular, the number of charge carriers as reflected in the parameter sigma(0) is shown to strongly correlate with the conductivity maxima as a function of lithium ion concentration. (C) 2003 The Electrochemical Society.

Monte Carlo calculations were carried out to simulate ion diffusion through polymer matrices. A dynamic bond percolation (DBP) model was employed that includes local harmonic motion of covalently bound anions in polyelectrolyte systems. The temperature dependence of cation diffusion was investigated in polyelectrolytes and polymer–salt complexes for 0–100 °C. Systems in which the rate of polymer reorganization is independent of temperature display Arrhenius behavior both above and below the Tg of 35 °C. Systems in which the temperature is coupled to the rate of polymer reorganization display VTF behavior above the Tg and near Arrhenius behavior below the Tg. In all cases, the temperature is coupled to the rate of successful ion jumps. Temperature and Tg seem to have no effect on the ion density at which the cation conductivity reaches a maximum.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNMR spectroscopic characterization of the two isomers of [HFe4(CO)13]-Colin P. Horwitz and Duward F. ShriverCite this: Organometallics 1984, 3, 5, 756–758Publication Date (Print):May 1, 1984Publication History Published online1 May 2002Published inissue 1 May 1984https://doi.org/10.1021/om00083a019RIGHTS & PERMISSIONSArticle Views70Altmetric-Citations17LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (360 KB) Get e-Alerts Get e-Alerts

The tosylate (p-toluenesulfonate) cluster [Bu4N]2[W6Cl8(p-OSO2C6H4CH3)6] (1) has been prepared and characterized by IR and NMR spectroscopy, elemental analysis, and an X-ray crystal structure. This cluster complex is shown to be a useful starting material for the preparation of pseudohalide clusters, [Bu4N]2[W6Cl8(NCQ)6] (Q = O (2), S (3), and Se (4)), in high yields. Cluster 1 also serves as a precursor to the new cluster compounds: [Bu4N]2[W6Cl8(O2CCH3)6] (5), [Bu4N]2[W6Cl8((mu-NC)Mn(CO)2(C5H5))6] (6), [W6Cl8((mu-NC)Ru(PPh3)2(C5H5))6][ p-OSO2C6H4CH3]4 (7), and [W6Cl8((mu-NC)Os(PPh3)2(C5H5))6][ p-OSO2C6H4CH3]4 (8). X-ray crystal structures are reported for 1, 4, and 5.

Amorphous electrolytes consisting of the lithium salts, Li[R-NSO2CF3] were prepared and the attendant low ionic conductivities of the lithium salt mixtures (∼1×10−6 S cm−1 at room temperature) are attributed to high glass transition temperatures. An example is the novel amorphous salt, Li[18-C-6NSO2CF3] which produces an amorphous salt mixture with Li[N(SO2CF3)2] (LiTFSI).

A series of polymer salt complexes based on poly(ethylene malonate) and lithium triflate were prepared with polymer repeat unit to cation ratios of 8, 4, 2, 1. These were characterized and then mixed with lithium triflate. The CO stretching peaks in the IR spectra of these polymers became broad when salt was introduced, indicating complex formation between the polymer and the lithium cation. Pure poly(ethylene malonate) has a glass transition at 258 K and the glass transition temperature increases with increasing salt concentration. The maximum room temperature ionic conductivity for this polymer/salt complex is 1.6×10−6 S/cm for a polymer repeat unit to cation ratio of 8, and the temperature dependence of the conductivity follows the Vogel–Tammann–Fulcher (VTF) equation.

The structure of the ambient temperature alkali metal molten salt system LiSCN/AlCl3 1:1 adduct was investigated by neutron diffraction, which demonstrates that the aluminum atom is surrounded by three chlorine atoms and one nitrogen atom, indicating the existence of the AlCl3NCS− anion, in which the NCS− coordinates to the Al center through nitrogen. Molecular orbital calculations using ab initio methods are also performed to study the optimized structures of the AlCl3NCS− and its isomer, AlCl3SCN−. The results are consistent with the neutron diffraction data and indicate that AlCl3NCS− is the major anionic complex in the 1:1 LiSCN/AlCl3 adduct.

: The series of investigations based on synthesis, physical characterization, charge transport measurements, and appropriate modeling studies has been completed, in the general area of polymer based electrolyte systems. Several substantive advances towards new, improved performance electrolyte materials both for low temperature fuel cell applications and for advanced secondary lithium battery materials have been reported. Particular advances in discovery areas include rigid polymer based electrolyte systems using carbonates, Lewis acid enhancement mechanisms for ionic conductivity in salts, optimization of local basicity and polyelectrolytes, and understanding of a phase diagram in mixed polymer complex polyelectrolyte structures.

An FT-Raman study was performed on lithium salt/polymer/nanosized inert oxide filler (SiO2, Al2O3) systems. Molecular spectroscopy suggests that there is little effect of the filler particles on the "free" anion/ion-pair/ higher aggregate equilibria. Raman line widths indicate enhanced anion disorder when a small amount of filler is introduced. Similarly, DSC measurement indicates a reduction of crystallinity. By contrast, fully amorphous polymer samples display broader Raman line widths and higher glass transition temperatures as the filler concentration is increased, with concomitant lower ion conductivity. The influence of the fillers differs in proportion to the extent of crystallinity of the polymer-salt complex, but within our experimental range the particle size or composition of the filler has little influence on ionic conductivity.

Complexes of lithium salts LiCF3SO3, LiI, LiCH3CO2, LiBF4, LiSCN, and Li[R-NSO2-CF3] with the macrocyclic ligands 18-C-6 and 2.2.2-cryptand were examined by differential scanning calorimetry, infrared and Raman spectroscopy, and complex impedance. The formation of an amorphous phase appears to be facilitated by the presence of an unsymmetrical anion containing an ether oxygen of the type [R-NSO2CF3](-). An X-ray crystal structure was determined for Li[CF3SO2N(CH2)(2)OCH3]; these data and that for the previously reported Li[CF3SO2N(CH2)(3)OCH3] structure was correlated with the physical properties of their 18-C-6 and 2.2.2-cryptand complexes.