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Three types of ladder-like organostannoxanes, [C5H4N(p-CO2)]2[Bu2Sn]4(μ3-O)2(μ2-OH)2 (1), [Ph2CHCO2]4[Bu2Sn]4(μ3-O)2 (2), and [(p-NH2)-C6H4-CO2]2[Bu2Sn]4(μ3-O)2(μ2-OH)2 (3), have been synthesized and characterized using elemental analyses, Fourier-transform infrared spectroscopy, nuclear magnetic resonance (1H, 13C) experiments, and, for 1 and 2, single-crystal X-ray diffraction analysis. X-Ray diffraction discloses that complexes adopt tetranuclear tin(iv) ladder-like structures containing two (1) or four (2) deprotonated ligands. The essential difference between their molecular structures is that in 2 there are four carboxylate ligands, while in 1 and 3 there are two. The crystal structure of 1 reveals them to be a tetranuclear structure containing a three-rung-staircase Sn4O4 core. The Sn4O4 cluster consists of a ladder of four Sn2O2 units. For 2, the structure is a tetranuclear centrosymmetric dimer of an oxoditin unit having a central four-member ring. In this complex, the central Sn2O2 core is fused with two four-member and two six-member rings. In the structures, there are two types of tin ions arranged in distorted trigonal bipyramid geometry or octahedron geometry. A series of O–H⋯N, C–H⋯O, and C–H⋯π intermolecular hydrogen bonds in these complexes play an important function in the supramolecular, or two-dimensional network structures are formed by these interactions.

The fabrication of nanostructured block copolymer (BCP) films endowed with lithium ion‐conducting gyroid (GYR) nanochannels is an appealing solution to build solid polymer electrolytes (SPEs) that combines high ionic conductivity (IC) with suitable mechanical properties. However, the formation of a well‐developed GYR structure remains challenging to achieve from the self‐assembly of polyelectrolyte BCP chains. To overcome this issue, large ion conducting gyroid grains were produced within freestanding polystyrene‐block‐poly(2‐vinylpyridine)‐block‐poly(ethylene oxide) (PS‐b‐P2VP‐b‐PEO) films by combining a solvent vapor annealing (SVA) treatment with an infiltration process. Here, the SVA treatment enabled the manufacture of SPEs entirely composed of a GYR structure while the infiltration process allowed for the incorporation of an appropriate Li salt (i.e., lithium iodoacetate, LiIAc) within the 3D‐interconected nanochannels via a Menshutkin reaction. By using this SVA‐Infiltration strategy, it has been demonstrated that the creation of ion conducting GYR nanochannels enhances the ion transportation capacity of pyridine‐containing SPEs since substantially lower ICs were measured from analog PS‐b‐P2VP‐b‐PEO/LiIAc films having a nominally disordered as‐cast state. Remarkably, zwitterionic pyridinium‐based moieties formed inside the interpenetrated nanochannels enable an efficient migration of Li+ and I3− species, leading to an IC as high as 10−4 S cm−1 at 70°C. [ABSTRACT FROM AUTHOR]

Artificial water channels (AWCs) have been extensively explored to mimic natural proteins, which enables to effectively transport water while blocking ions. As one of the first AWCs, self‐assembled I‐quartets (HCx) have showcased high water‐permselectivity that can be enhanced by improving their distribution and stability within membrane. The use of long alkyl chains (n>8) is constrained by their low solubility and aggregation. Herein, we considered cycloalkyl moieties, explored for the increase of the solubility favoring enhanced partition and/ for their self‐assembly behaviors resulting the formation of effective stable water‐channels with increased water permeability in bilayer membranes. This class of cycloalkyl‐ureido‐ethyl‐imidazole amphiphilic (CxUH) channel could serve as a new reference for the effective design of self‐assembled artificial water channels, it may give rise to the applications in desalination or in water treatment. [ABSTRACT FROM AUTHOR]

Pyrene boxes, self‐assembled from 1,3,5,8‐pyrene‐tetrasulfonate anions, PTS4− and Guanidinium G+, amino‐guanidinium AG+ and hydrated alkali counter cations have been used for the encapsulation of 1,ω‐amino‐acids of variable lengths. The NMR spectroscopy illustrates that these systems are stable in aqueous solution and encapsulation process involves dynamic or fixed guest molecules within Pyrene box, depending of the nature of the counter‐cations. The amide bond coupling between the amino‐guanidinium AG+ and encapsulated 1,ω‐amino‐acid guests occur in water in the absence of coupling catalysts. The variable co‐encapsulation of the guests via multivalent stabilizing interactions shed light that chemical selection can be obtained from mixtures of 1,ω‐amino‐acids. Our study involving a comprehensive screening of 18 co‐crystal structures help to understand the in‐situ fixation of 1,ω‐amino‐acid guests and their accurate determination of unconventional structures under confinement. [ABSTRACT FROM AUTHOR]

The synthesis of catalytic materials containing active sites of various oxidation states (metal, oxide, etc.) for the dual use in reduction and oxidation reactions remains challenging because most of the reported methods for the metallic state are often incompatible with those for the oxide state. A new methodology is reported for the synthesis of a library of bimetallic metal‐oxide materials containing three crystalline phases Ir‐Ru‐IrxRu1‐xO2 by combining the calcination under air and the polymerization of aniline in the presence of IrCl3 and RuCl3 precursors. Morphology, structure, and surface oxidation state studies (XRD, SEM/EDX, S/TEM, XPS) confirm the hypothesis that IrCl3 evolves to Ir while RuCl3 evolves to RuO2 during the calcination under air. An Ir:Ru atomic ratio of 50:50 can be converted into a heterogeneous nanostructure composed of Ir, Ru, and IrxRu1‐xO2 to date, with remarkable catalytic activity for both hydrogen evolution reaction (HER) with a small overpotential of 40 mV and oxygen evolution reaction (OER) with a small overpotential of 290 mV at the metric current density of 10 mA cm−2 in 0.5 m H2SO4. The results can serve as a platform for the development of efficient multifunctional materials for practical use in both catalytic oxidation and reduction reactions. [ABSTRACT FROM AUTHOR]

Understanding water transport mechanisms at the nanoscale level remains a challenge for theoretical chemical physics. Major advances in chemical synthesis have allowed us to discover new artificial water channels, rivaling with or even surpassing water conductance and selectivity of natural protein channels. In order to interpret experimental features and understand microscopic determinants for performance improvements, numerical approaches based on all-atom molecular dynamics simulations and enhanced sampling methods have been proposed. In this study, we quantify the influence of microscopic observables, such as channel radius and hydrogen bond connectivity, and of meso-scale features, such as the size of self-assembly blocks, on the permeation rate of a self-assembled nanocrystal-like artificial water channel. Although the absolute permeation rate extrapolated from these simulations is overestimated by one order of magnitude compared to the experimental measurement, the detailed analysis of several observed conductive patterns in large assemblies opens new pathways to scalable membranes with enhanced water conductance for the future design. [ABSTRACT FROM AUTHOR]