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Elastomeric stamp deformation was used to fabricate a series of new metal thin film patterns not present on the original stamp. The rounded patterns are of nanoscale thickness, long-range order, and are created from elastomeric stamps with only straight-edged features and the feature size, separation, relief height, stamp elasticity and external force control the morphology and appearance of shape.

The crystal structure, thermal properties and magnetic properties of a three-dimensional (3D) metal-organic open framework, with infinite one-dimensional (1D) Cu(II) oxide chains embedded in the structure are described. The studies indicate that the framework is a 1D antiferromagnetic system with a Neel temperature of 51 K and a paramagnetic impurity dominates the susceptibility below 14 K, implying the synthesized compound to be highly pure.

Research has been conducted on layered lead phenylphosphonates. The authors discuss the solvothermal synthesis and characterization of these compounds.

We describe herein a three-dimensional Cu(II) based metal−organic framework, copper hydroxide 2,6-naphthalenedisulfonate, Cu3(OH)4[C10H6(SO3)2]. The compound contains embedded positively charged 2-D copper oxide layers. This higher dimensionality of inorganic connectivity leads to far greater thermal stability (375 °C vs 245 °C) over our previously reported three-dimensional metal−organic framework containing embedded 1-D cuprate chains. Single crystal data for this material are as follows: FW = 544.92, monoclinic, space group P21/c, a = 13.549(5) Å, b = 5.503(2) Å, c = 9.512(4) Å, β = 90.031(6)°, V = 709.2(5) Å3, Dc = 2.552 g·cm−3, and Z = 4. The structure, crystallinity, morphology, and properties of the material are discussed. The magnetic susceptibility exhibits a broad maximum centered at 80 K, indicative of low-dimensional antiferromagnetic interactions. Control of inorganic dimensionality embedded within an MOF is an often overlooked yet key feature in determining the stability and important properties of MOFs such as adsorption, conductivity, and magnetism. A three-dimensional Cu(II) based metal−organic framework, copper hydroxide 2,6-naphthalenedisulfonate, is described. The compound contains embedded cationic 2-D copper oxide layers, with greater thermal stability over our previously reported three-dimensional MOF containing embedded cationic 1-D cuprate chains. Control of inorganic dimensionality embedded within an MOF is an often overlooked yet key feature in determining important properties of MOFs such as adsorption, conductivity, and magnetism. [ABSTRACT FROM AUTHOR]

Focuses on the development of Pb[sub 3]F[sub 5]NO[sub 3], a cationic layered material for anion-exchange. Structures of layered material; Factors affecting the stability of material temperature; Growth of anionic clusters within the void space of cationic material.

Examines the photophysical and photochemical properties of W(O) and Re(I) carbonyl complexes. Use of special redox-active features to develop electrochemical sensors; Focus on homonuclear ferrocenes different organic spacers; Photophysical and photochemical properties of polypyridyl d[sup 6]-metal(W[sup 0] and Re[sup I]) carbonyl complexes.

The ability to control the surface composition and morphology of alloy catalysts is critical for achieving high activity and durability of catalysts for oxygen reduction reaction (ORR) and fuel cells. This report describes an efficient surfactant-free synthesis route for producing a twisty nanowire (TNW) shaped platinum-iron (PtFe) alloy catalyst (denoted as PtFe TNWs) with controllable bimetallic compositions. PtFe TNWs with an optimal initial composition of ∼24% Pt are shown to exhibit the highest mass activity (3.4 A/mg Pt , ∼20 times higher than that of commercial Pt catalyst) and the highest durability (<2% loss of activity after 40 000 cycles and <30% loss after 120 000 cycles) among all PtFe-based nanocatalysts under ORR or fuel cell operating conditions reported so far. Using ex situ and in situ synchrotron X-ray diffraction coupled with atomic pair distribution function (PDF) analysis and 3D modeling, the PtFe TNWs are shown to exhibit mixed face-centered cubic (fcc)-body-centered cubic (bcc) alloy structure and a significant lattice strain. A striking finding is that the activity strongly depends on the composition of the as-synthesized catalysts and this dependence remains unchanged despite the evolution of the composition of the different catalysts and their lattice constants under ORR or fuel cell operating conditions. Notably, dealloying under fuel cell operating condition starts at phase-segregated domain sites leading to a final fcc alloy structure with subtle differences in surface morphology. Due to a subsequent realloying and the morphology of TNWs, the surface lattice strain observed with the as-synthesized catalysts is largely preserved. This strain and the particular facets exhibited by the TNWs are believed to be responsible for the observed activity and durability enhancements. These findings provide new insights into the correlation between the structure, activity, and durability of nanoalloy catalysts and are expected to energize the ongoing effort to develop highly active and durable low-Pt-content nanowire catalysts by controlling their alloy structure and morphology.

In this study, we demonstrate a non-Pt nanostructured bioinorganic hybrid (BIH) catalyst for catalytic oxygen reduction in alkaline media. This catalyst was synthesized through biomaterial hemin, nanostructured Ag-Co alloy, and graphene nano platelets (GNP) by heat-treatment and ultrasonically processing. This hybrid catalyst has the advantages of the combined features of these bio and inorganic materials. A 10-fold improvement in catalytic activity (at 0.8 V vs RHE) is achieved in comparison of pure Ag nanoparticles (20-40 nm). The hybrid catalyst reaches 80% activity (at 0.8 V vs RHE) of the state-of-the-art catalyst (containing 40% Pt and 60% active carbon). Comparable catalytic stability for the hybrid catalyst with the Pt catalyst is observed by chronoamperometric experiment. The hybrid catalyst catalyzes 4-electron oxygen reduction to produce water with fast kinetic rate. The rate constant obtained from the hybrid catalyst (at 0.6 V vs RHE) is 4 times higher than that of pure Ag/GNP catalyst. A catalytic model is proposed to explain the oxygen reduction reaction at the BIH catalyst.

Elastomeric stamp deformation has been utilized for the contact printing (CP) of self-assembled monolayers (SAMs) and, more recently, polymers and proteins. Here, we take advantage of this well-studied phenomenon to fabricate a series of new metal thin-film patterns not present on the original stamp. The rounded patterns are of nanoscale thickness, long-range order, and are created from elastomeric stamps with only straight-edged features. The metal was printed onto the surface of an alpha,omega-alkanedithiol self-assembled monolayer (SAM). The new shapes are controlled by a combination of stamp geometry design and the application of external pressure. Previously published rules on stamp deformation for contact printing of SAMs are invalid because the coating is instead a thin-metal film. This method represents a new pathway to micropatterning metal thin films, leading to shapes with higher complexity than the original lithographic masters.