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Ion and electron transport is of paramount importance for solid‐state technology and its limitation presently prevents the access to liquid cells performance. Herein, this work tackles this issue by proposing an easily implementable cell design enabling to follow the cathode composite's electronic conductivity evolution, in situ and during cycling. For proof of concept, distinct active material (AM) based composites are studied, namely LiCoO2 (LCO), LiNiO2, LiNi0.9Co0.1O2 (NC 9010), NMC 811, NMC 622, NMC 111 (NMC family: LiNi1‐yMnyCoyO2), and Li4Ti5O12 (LTO) mixed with Li6PS5Cl solid electrolyte (SE). This work shows the feasibility to track AM's phase transitions associated with changes in the material's electronic transport properties. Moreover, this work demonstrates the impact of the Ni content in the various layered oxides, on the interparticle loss of contact at high state‐of‐charge affecting electronic transport. Lastly, by tuning LTO particle size and morphology, this work shows the effect of primary and secondary particle size on the specific metal–insulator transition pertaining to this material. Altogether, this new testing cell opens‐up a broad spectrum of experimental possibilities aiming to access in situ mode key metrics to benefit the optimization of solid‐state batteries research. [ABSTRACT FROM AUTHOR]

Mixed‐anion compounds widen the chemical space of attainable materials compared to single anionic compounds, but the exploration of their structural diversity is limited by common synthetic paths. Especially, oxychlorides rely mainly on layered structures, which suffer from low stability during photo(electro)catalytic processes. Herein we report a strategy to design a new polar 3D tetrahedral framework with composition Zn4Si2O7Cl2. We use a molten salt medium to enable low temperature crystallization of nanowires of this new compound, by relying on tetrahedral building units present in the melt to build the connectivity of the oxychloride. These units are combined with silicon‐based connectors from a non‐oxidic Zintl phase to enable precise tuning of the oxygen content. This structure brings high chemical and thermal stability, as well as strongly anisotropic hole mobility along the polar axis. These features, associated with the ability to adjust the transport properties by doping, enable to tune water splitting properties for photoelectrocatalytic H2 evolution and water oxidation. This work then paves the way to a new family of mixed‐anion solids [ABSTRACT FROM AUTHOR]

The crystal structure of tooeleite, [Fe.sub.6][(As[O.sub.3]).sub.4](S[O.sub.4])[(OH).sub.4] x 4[H.sub.2]O, has been solved from high-resolution synchrotron XRD powder data recorded on a sample from Tooele county, Utah. The structure is monoclinic, space group C2/m, a = 8.9575(1), b = 6.4238(1), c = 9.7912(1) [Angstrom], [beta] = 96.032(1)[degrees], V = 560.27(3)[[Angstrom].sup.3], [d.sub.cale] = 3.16 g/[cm.sup.3]. The structure was solved by direct methods and atomic positions, site occupancies, and isotropic displacement parameters were refined by the Rietveld method. The As[O.sub.3] pyramids bond to Fe[O.sub.6] octahedra by both edge- and corner-linkage, forming layers that intercalate S[O.sub.4] groups. Assignment of structural [H.sub.2]O and OH groups were done from bond-valence analysis. Tooeleite is the only arsenite-sulfate mineral known and has been recently identified as the main constituent of stromatolite-like deposits in the Carnoules acid mine, Gard, France. Keywords: Crystal structure, tooeleite, XRD data, synchrotron powder diffraction, new minerals, geomicrobiology, acid mine drainage

The present work reports on a new type of V‐based catalysts, namely V‐substituted hydroxyapatites, and the influence of the synthesis conditions on their catalytic performance in the oxidative dehydrogenation of propane (ODHP) reaction. Vx‐substituted hydroxyapatite materials prepared with the periodic addition of ammonia during the maturation step (Vx‐HAp‐pH‐per) were shown to exhibit a Ca4V4O14 phase in addition to the V‐substituted hydroxyapatite phase for x greater than or equal to 3.5. TEM characterization of the biphasic samples allowed us to demonstrate that the Ca4V4O14 phase was grown epitaxially on the Vx‐HAp nanorods. The close intimacy between the two phases was confirmed by NMR suggesting the involvement of V4+ species. Consistently EPR data of the fresh and spent samples showed that V4+ species may be stabilized at the boundaries of these two phases. The strong promotion of the oxidative dehydrogenation reaction to propene observed from 723 K for the V4‐HAp‐pH‐per composition is attributed to a synergistic effect between the Vx‐HAp nanorods that enable the activation of propane and the Ca4V4O14 phase that helps the redox exchanges. This synergy may be attributed to an easier electron delocalization on the V4O14 units located at the phases' boundaries. [ABSTRACT FROM AUTHOR]

Solid‐state batteries are enjoying a regained interest owing to the discovery of sulfide‐based solid electrolytes with ionic conductivities comparable to their liquid counterparts. Among them, the metastable β‐Li3PS4 polymorph has attracted great attention given its high room temperature ionic conductivity (≈0.15 mS cm−1) when synthesized via a solvent‐mediated route. However, the origin of such a high conductivity together with its structural interplay remains unclear. Herein, an in‐depth study of the THF‐synthesized nanoporous β‐Li3PS4 is reported. Synchrotron X‐ray diffraction, NMR, and Raman spectroscopy confirm the presence of β‐Li3PS4 as the only crystalline phase and also reveal an additional amorphous phase and remnant THF. Moreover, a clear dependence of the ionic conductivity of the material on the relative content of its phases is found, the amorphous one being the most conductive. Lastly, high chemical reactivity is found for the nanoporous β‐Li3PS4 and other phosphosulfide electrolytes toward Li metal, evidenced in the spontaneous ignition when mixed together and further investigated by XRD and XPS. This study, which unveils a hidden side of the THF‐synthesized β‐Li3PS4 and other sulfide solid electrolytes, provides a new insight to the battery community when selecting a proper electrolyte for practical all‐solid state batteries. [ABSTRACT FROM AUTHOR]