A new type of polymer electrolyte material for Li ion transport has been developed. This material is based on a polymerizable lyotropic (i.e., amphiphilic) liquid crystal (1) that forms a type-II bicontinuous cubic (Q(II)) phase with the common liquid electrolyte, propylene carbonate (PC), and its Li salt solutions. The resulting cross-linked, solid-liquid nanocomposite has an ordered, three-dimensional interconnected network of phase-separated liquid PC nanochannels and exhibits a room-temperature ion conductivity of 10(-4) to 10(-3) S cm(-1) when formed with 15 wt % 0.245 M LiClO(4)-PC solution. This value approaches that of conventional gelled poly(ethylene oxide)-based electrolytes blended with larger amounts of higher-concentration Li salt solutions. It is also similar to that of a bulk 0.245 M LiClO(4)-PC solution measured using the same AC impedance methods. Preliminary variable-temperature ion conductivity and NMR DOSY studies showed that liquidlike diffusion is present in the Q(II) nanochannels and that good ion conductivity ( approximately 10(-4) S cm(-1)) and PC mobility are retained down to -35 degrees C (and lower). This type of stable, liquidlike ion conductivity over a broad temperature range is typically not exhibited by conventional gelled-polymer- or liquid-crystal-based electrolytes, making this new material potentially valuable for enabling Li ion batteries that can operate more efficiently over a wider temperature range.

Organic, nanoporous heterogeneous catalysts based on a carboxylate-containing, amphiphilic mesogen catalyze the Knoevenagel condensation (see schematic representation). These networks maintain their order in solution and can be recycled. Enhanced basicity, excellent site accessibility, and substrate size exclusion are features of these nanostructured systems.

Molecular dynamics simulations of fluoroalkyl-derivatized imidazolium:bis(trifluoromethylsulfonyl)imide (TFSI) room temperature ionic liquids (FADI-RTILs) with cations of the structure 1-F(CF(2))(n)(CH(2))(2)-3-methyl imidazolium have been performed and compared with simulations of alkyl-derivatized 1-H(CH(2))(n+2)-3-methyl imidazolium analogs (ADI-RTILs). Simulations yield RTIL densities, viscosities and ionic conductivities for the FADI-RTILs and ADI-RTILs in reasonably good agreement with experimental data. Partial fluorination results in a larger increase in density than would be anticipated based upon the density difference between perfluoralkane and alkane melts. Similarly, the slowing down in dynamics upon partial fluorination is greater than would be expected based upon the increase in cation volume. Examination of cation-cation, anion-anion and cation-anion centers-of-mass radial distribution functions reveal remarkably little influence of partial fluorination on the spherically averaged intermolecular structure of the RTILs. Similarly, simulations reveal little change in tail conformations and the extent of tail-tail aggregation upon partial fluorination. The interaction of the TFSI anion with the positively charged imidazolium ring hydrogen and nitrogen atoms is also little influenced by partial fluorination. However, the partially fluorinated alkyl tail exhibits increased interaction with the TFSI anion due to the electron withdrawing character of the fluorinated groups. We believe this strong tail-anion electrostatic interaction largely accounts for the higher than expected density and slower than expected dynamics in the FADI-RTILs.

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