Room-temperature-ionic-liquid coated graphitized carbons for selective preconcentration of polar vapors.

Most adsorbent materials used for preconcentrating and thermally desorbing volatile and semi-volatile organic compounds (S/VOCs) in portable or "micro" gas chromatographic (GC/µGC) instruments preferentially capture non-polar or moderately polar compounds relative to more polar compounds. Here, we explore the use of a known trigonal-tripyramidal room-temperature ionic liquid (RTIL) as a surface modifier for the graphitized carbons, Carbopack B (C-B) and Carbopack X (C-X), with the goal of enhancing their capacity and selectivity for polar S/VOCs. Breakthrough tests were performed by challenging tubes packed with ∼2.

The Influence of Chemical Modification on Linker Rotational Dynamics in Metal-Organic Frameworks.

The robust synthetic flexibility of metal-organic frameworks (MOFs) offers a promising class of tailorable materials, for which the ability to tune specific physicochemical properties is highly desired. This is achievable only through a thorough description of the consequences for chemical manipulations both in structure and dynamics. Magic angle spinning solid-state NMR spectroscopy offers many modalities in this pursuit, particularly for dynamic studies.

Rapid Guest Exchange and Ultra-Low Surface Tension Solvents Optimize Metal-Organic Framework Activation.

Exploratory research into the critical steps in metal-organic framework (MOF) activation involving solvent exchange and solvent evacuation are reported. It is discovered that solvent exchange kinetics are extremely fast, and minutes rather days are appropriate for solvent exchange in many MOFs. It is also demonstrated that choice of a very low surface tension solvent is critical in successfully activating challenging MOFs.

Effect of Interfacial Molecular Orientation on Power Conversion Efficiency of Perovskite Solar Cells.

A wide variety of charge carrier dynamics, such as transport, separation, and extraction, occur at the interfaces of planar heterojunction solar cells. Such factors can affect the overall device performance. Therefore, understanding the buried interfacial molecular structure in various devices and the correlation between interfacial structure and function has become increasingly important.

A Perylene-Based Microporous Coordination Polymer Interacts Selectively with Electron-Poor Aromatics.

The design, synthesis, and properties of the new microporous coordination polymer UMCM-310 are described. The unique electronic character of the perylene-based linker enables selective interaction with electron-poor aromatics leading to efficient separation of nitroaromatics. UMCM-310 possesses high surface area and large pore size and thus permits the separation of large organic molecules based on adsorption rather than size exclusion.

A non-regular layer arrangement of a pillared-layer coordination polymer: avoiding interpenetration via symmetry breaking at nodes.

A coordination terpolymerization strategy is introduced to alter the connectivity within layers of a pillared-layer coordination polymer. Assembling two different dicarboxylate linkers around a metal cluster in the layer suppresses interpenetration while enabling formation of a rectangular 2D grid structure.

The Role of Modulators in Controlling Layer Spacings in a Tritopic Linker Based Zirconium 2D Microporous Coordination Polymer.

A 2D zirconium-based microporous coordination polymer derived from the tritopic linker 1,3,5-(4-carboxylphenyl)benzene, UMCM-309a, has been synthesized. This noninterpenetrated material possesses a Zr6(μ3-O)4(μ3-OH)4(RCO2)6(OH)6(H2O)6 cluster with six hexagonal-planar-coordinated linkers. UMCM-309a is stable in an aqueous HCl solution for over 4 months.