Highly Selective Li + Ion Transport by Porous Molybdenum‐Oxide Keplerate‐Type Nanocapsules Integrated in a Supported Liquid Membrane

Synthesis of Molybdenum Blue Dispersions Using Ascorbic Acid as Reducing Agent

Stable molybdenum blue nanoparticles dispersions were synthesized using ammonium heptamolybdate and ascorbic acid. The effect of molar ratios of reducing agent/Mo and acid/Mo on the speed of formation and stability of the disperse system has been demonstrated. The particles were characterized by UV/vis, infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, and dynamic light scattering (DLS) methods. The X-ray photoelectron spectroscopy (XPS) method confirmed the presence of reduced MoV in the structure of molybdenum oxide nanoclusters, the proportion of which was 30%.

Coordinative interaction between nitrogen oxides and iron–molybdenum POM Mo72Fe30

The process of adsorption of nitrogen monoxide and dioxide by the giant Keplerate nanocluster Mo₇₂Fe₃₀ was studied in detail under ambient conditions and air/argon atmosphere.

Biomimetic Approach for Ion Channels Based on Surfactant Encapsulated Spherical Porous Metal-Oxide Capsules

Distinguished hybrid clusters with hydrophilic and hydrophobic interiors embedded within cationic surfactant shells are spontaneously inserted into lipid bilayers, showing well-defined ionic conductance behaviors. The transport via the narrow pore gates acting as selectivity filters is controlled by the dehydration energy of the cations.

A unique fluoride nanocontainer: porous molecular capsules can accommodate an unusually high number of "rather labile" fluoride anions

The present work refers to the challenging issue of fluoride anion recognition/binding in water by taking advantage of the unique possibilities offered by the porous molecular nanocontainers of the {Mo132} Keplerate type allowing the study of a variety of new phenomena. Reaction of the highly reactive carbonate-type capsule with aqueous HF results in the release of carbon dioxide and integration of an unprecedentedly large number of fluoride anions--partly as coordinated ligands at both the pentagonal units and the linkers, partly as a disordered water/fluoride assembly inside the cavity. The internal assembly and some of the fluoride ligands are easily released, which provides interesting options for future studies regarding coordination chemistry and catalysis under confined conditions.

Perspectives in chemistry--aspects of adaptive chemistry and materials

Chemistry, pure and applied, is a science and an industry. By its power over the expressions of matter, it also displays the creativity of art. It has expanded from molecular to supramolecular chemistry and then, by way of constitutional dynamic chemistry, towards adaptive chemistry. Constitutional dynamics allow for adaptation, through component exchange and selection in response to physical stimuli (e.g. light, photoselection), to chemical effectors (e.g. metal ions, metalloselection) or to environmental effects (e.g. phase change) in equilibrium or out-of-equilibrium conditions, towards the generation of the best-adapted/fittest constituent(s) in a dynamic set. Such dynamic systems can be represented by two-dimensional or three-dimensional dynamic networks that define the agonistic and antagonistic relationships between the different constituents linked through component exchange. The introduction of constitutional dynamics into materials science opens perspectives towards adaptive materials and technologies, presenting attractive behavioral features (such as self-healing). In particular, dynamic polymers may undergo modification of their properties (mechanical, optical, etc.) through component exchange and recombination in response to physical or chemical agents. Constitutional adaptive materials open towards a systems materials science and offer numerous opportunities for soft-matter technologies.

Multivalent recognition of concanavalin A by {Mo₁₃₂ } glyconanocapsules--toward biomimetic hybrid multilayers

Herein, we consider Müller's spherical, porous, anionic, molybdenum oxide based capsule, (NH4)42[{(Mo(VI))Mo(VI)5O21(H2O)6}12{Mo(V)2O4(CH3COO)}30]⋅10 CH3COONH4⋅300 H2O≡(NH4)42⋅1 a⋅crystal ingredients≡1, {Mo132}, as an effective sugar-decorated nanoplatform for multivalent lectin recognition. The ion-exchange of NH4(+) ions of 1 with cationic-sugars, D-mannose-ammonium chloride (2) or D-glucose-ammonium chloride (3) results in the formation of glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a. The Mannose (NH4)(42-n)2n⋅1 a capsules bind selectively Concanavalin A (Con A) in aqueous solution, giving an association avidity constant of K(a)(multi)=4.6×10(4) M(-1) and an enhancement factor of β=K(a)(multi)/K(ass)(mono)=21.9, reminiscent of the formation of "glycoside clusters" on the external surface of glyconanocapsule. The glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a self-assemble in "hybrid multilayers" by successive layer-by-layer deposition of (NH4)(42-n)2n⋅1 a or (NH4)(42-m)3m⋅1 a and Con A. These architectures, reminiscent of versatile mimics of artificial tissues, can be easily prepared and quantified by using quartz crystal microgravimetry (QCM). The "biomimetic hybrid multilayers" described here are stable under a continual water flow and they may serve as artificial networks for a greater depth of understanding of various biological mechanisms, which can directly benefit the fields of chemical separations, sensors or storage-delivery devices.

A light-induced reversible phase separation and its coupling to a dynamic library of imines

Irradiation of an acetonitrile–water solution of the bis-pyridyl hydrazone 1 and calcium chloride causes a photo-induced phase separation. It is coupled to a covalent library of imines, undergoing constitutional reorganization upon phase separation.