One key tenet of the raft hypothesis is that the formation of glycosphingolipid- and cholesterol-rich lipid domains can be driven solely by characteristic lipid-lipid interactions, suggesting that rafts ought to form in model membranes composed of appropriate lipids. In fact, domains with raft-like properties were found to coexist with fluid lipid regions in both planar supported lipid layers and in giant unilamellar vesicles (GUVs) formed from 1) equimolar mixtures of phospholipid-cholesterol-sphingomyelin or 2) natural lipids extracted from brush border membranes that are rich in sphingomyelin and cholesterol. Employing headgroup-labeled fluorescent phospholipid analogs in planar supported lipid layers, domains typically several microns in diameter were observed by fluorescence microscopy at room temperature (24 degrees C) whereas non-raft mixtures (PC-cholesterol) appeared homogeneous. Both raft and non-raft domains were fluid-like, although diffusion was slower in raft domains, and the probe could exchange between the two phases. Consistent with the raft hypothesis, GM1, a glycosphingolipid (GSL), was highly enriched in the more ordered domains and resistant to detergent extraction, which disrupted the GSL-depleted phase. To exclude the possibility that the domain structure was an artifact caused by the lipid layer support, GUVs were formed from the synthetic and natural lipid mixtures, in which the probe, LAURDAN, was incorporated. The emission spectrum of LAURDAN was examined by two-photon fluorescence microscopy, which allowed identification of regions with high or low order of lipid acyl chain alignment. In GUVs formed from the raft lipid mixture or from brush border membrane lipids an array of more ordered and less ordered domains that were in register in both monolayers could reversibly be formed and disrupted upon cooling and heating. Overall, the notion that in biomembranes selected lipids could laterally aggregate to form more ordered, detergent-resistant lipid rafts into which glycosphingolipids partition is strongly supported by this study.

In the search for novel solid electrolytes for solid-state batteries, thiophosphate ionic conductors have been in recent focus owing to their high ionic conductivities, which are believed to stem from a softer, more polarizable anion framework. Inspired by the oft-cited connection between a soft anion lattice and ionic transport, this work aims to provide evidence on how changing the polarizability of the anion sublattice in one structure affects ionic transport. Here, we systematically alter the anion framework polarizability of the superionic argyrodites LiPSX by controlling the fractional occupancy of the halide anions (X = Cl, Br, I). Ultrasonic speed of sound measurements are used to quantify the variation in the lattice stiffness and Debye frequencies. In combination with electrochemical impedance spectroscopy and neutron diffraction, these results show that the lattice softness has a striking influence on the ionic transport: the softer bonds lower the activation barrier and simultaneously decrease the prefactor of the moving ion. Due to the contradicting influence of these parameters on ionic conductivity, we find that it is necessary to tailor the lattice stiffness of materials in order to obtain an optimum ionic conductivity.

All-solid-state lithium ion batteries may become long-term, stable, high-performance energy storage systems for the next generation of electric vehicles and consumer electronics, depending on the compatibility of electrode materials and suitable solid electrolytes. Nickel-rich layered oxides are nowadays the benchmark cathode materials for conventional lithium ion batteries because of their high storage capacity and the resulting high energy density, and their use in solid-state systems is the next necessary step. In this study, we present the successful implementation of a Li­[Ni,Co,Mn]­O2 material with high nickel content (LiNi0.8Co0.1Mn0.1O2, NCM-811) in a bulk-type solid-state battery with β-Li3PS4 as a sulfide-based solid electrolyte. We investigate the interface behavior at the cathode and demonstrate the important role of the interface between the active materials and the solid electrolyte for the battery performance. A passivating cathode/electrolyte interphase layer forms upon charging and leads to an irreversible first cycle capacity loss, corresponding to a decomposition of the sulfide electrolyte. In situ electrochemical impedance spectroscopy and X-ray photoemission spectroscopy are used to monitor this formation. We demonstrate that most of the interphase formation takes place in the first cycle, when charging to potentials above 3.8 V vs Li+/Li. The resulting overvoltage of the passivating layer is a detrimental factor for capacity retention. In addition to the interfacial decomposition, the chemomechanical contraction of the active material upon delithiation causes contact loss between the solid electrolyte and active material particles, further increasing the interfacial resistance and capacity loss. These results highlight the critical role of (electro-)­chemo-mechanical effects in solid-state batteries.

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We examined the physical and chemical characteristics of transient confinement zones (TCZs) that are detected in single particle trajectories of molecules moving within the membrane of C3H 10T1/2 murine fibroblasts and their relationship to "rafts." We studied the lateral movement of different membrane molecules thought to partition to varying degrees into or out of the putative lipid domains known as rafts. We found that lipid analogs spend significantly less time in TCZs compared with Thy-1, a glycosylphosphatidylinositol-anchored protein, and GM1, a glycosphingolipid. For Thy-1, we found that zone abundance was markedly reduced by cholesterol extraction, suggesting that a major source of the observed temporary confinement is related to the presence of raft domains. More detailed analysis of particle trajectories reveals that zones can be revisited even tens of seconds after the original escape and that diffusion within the zones is reduced by a factor of approximately 2, consistent with the zone being a cholesterol-rich liquid-ordered phase. Surprisingly, transient confinement was not strongly temperature dependent. Overall, our data demonstrate that there are raft-related domains present in certain regions of the plasma membrane of C3H cells, which can persist for tens of seconds.

In situ X-ray photoelectron spectroscopy shows the redox-active chemistry of β-Li3PS4 at the cathode interface in a solid-state battery.

The local structure phase diagram of (Li2S)x(P2S5)100−x thiophosphates derived from pair distribution function crystallization experiments.

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