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We report the crystal structures of four different neutral lanthanide (Ln = La, Nd, Eu and Gd) metal–organic frameworks based on the organic linker 2,6-naphthalenedicarboxylate (NDC). The materials are three-dimensional and crystallize in three distinct topologies, with distinct bonding modes of NDC and lanthanide coordination numbers ranging from seven to nine and varying geometry. We denote our materials SLUG-49 [La6(NDC)9(DMF)3·6 DMF], -50 [Nd2(NDC)3O(DMF)2], -51 [Eu2(NDC)3(DMF)2·DMF], and -52 [Gd4(NDC)6(DMF)4] (DMF = N,N-dimethylformamide). The structures exhibit similar thermal decomposition profiles and infrared spectra. The Eu(III)-based material exhibits a sharp red-orange luminescence at 613 nm with a quantum efficiency of 3.56%.

We report the structures of six anionic, isomorphous metal–organic frameworks [Ln(bpdc)2–][NH2(CH3)2+], where Ln = La, Ce, Nd, Eu, Gd, Er, and bpdc2– = biphenyl-4,4′-dicarboxylate = –O2C(C6H4)2CO2–...

We present the rapid synthesis of a series of metal–organic framework (MOF) thin films on indium tin oxide (ITO) glass. ITO was first electrodeposited with either copper or zinc microcrystalline fi...

Large Fe3O4@SiO2 nanoparticles (∼200 nm) functionalized with gold and poly(vinylpyrrolidone) have been synthesized, characterized, and evaluated for bioseparation and sensing applications. The particles have been characterized using a combination of experimental techniques including ultraviolet visible spectroscopy, energy-dispersive spectroscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, electron microscopy, superconducting quantum interference device magnetrometry, and surface-enhanced Raman sensing (SERS) spectroscopy. The particles have a unique surface morphology comprised of roughened gold nodules. The surface coatings prevent oxidation and render the particles easy to functionalize in order to target a wide range of moieties. The gold coverage is not only uniform across the entire particle surface but also ultrathin so as to maintain a high percentage of the cores magnetic saturation (∼68%) when compared to that of bare magnetite. The gold nodules facilitate the generation ...

The desulfurization of JP-8 (Jet Propellant 8) fuel is of interest to the U.S. military because of its potential use as a fuel source for solid oxide fuel cells (SOFCs). SOFCs can be used to supply a steady stream of power during military silent watch missions. Adsorptive desulfurization is a promising alternative to hydrodesulfurization, which is unable to remove refractory sulfur compounds and achieve the ultra-low sulfur levels necessary to prevent poisoning of SOFCs. Adsorptive desulfurization could be a portable, on-site process performed on JP-8 stocks already in the field. Within the vast field of fuel processing/reformation, herein we focus on the current status of adsorptive desulfurization performed on JP-8 jet fuel. Currently, the best performing sorbents are those utilizing high surface area porous frameworks with pore sizes large enough to accommodate sulfur contaminants. Additionally, a variety of metals in ionic, metallic, and oxide form serve as promising active sites within these sorbents. Most reports focus on reformation technologies and sorbent materials for gas-phase desulfurization and hydrogen purification of low-sulfur content diesel or light fraction jet fuel. JP-8 is unique to the Army in terms of supply. This review will thus focus on ongoing efforts in the room temperature liquid desulfurization of JP-8 and its higher levels of impurities that are more complex and difficult to remove.

An amorphous nickel and boron composite (NBC) was synthesized from nickel chloride hexahydrate (NiCl2·6H2O) and sodium borohydride (NaBH4) in absolute ethanol, both in bulk and supported on mesoporous aluminosilicate nanoparticles (MASN). Comparatively, NBC-MASN demonstrated better catalytic activity for the selective reduction of the nitro group on a variety of polysubstituted nitroarenes, using hydrazine hydrate (N2H4·H2O) as the reducing agent at 25 °C. Reuse and regeneration of NBC-MASN for the reduction of p-nitrotoluene to p-toluidine were studied with NaBH4 acting as a regeneration agent. Good catalytic activity was sustained through nine reuse cycles when equimolar NaBH4 was present in situ with N2H4·H2O (99%-67% isolated aniline yield). The structure and composition of NBC and NBC-MASN were examined by electron microscopy, energy dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and inductively coupled plasma optical emission spectroscopy (ICP-OES). The results for NBC-MASN show that a thin (

© 2019 American Chemical Society. Oxygen evolution reaction (OER) involves multiple electron-transfer processes, resulting in a high activation barrier. Developing catalysts with low overpotential and high intrinsic activity toward OER is critical but challenging. Here we report a major advancement in decreasing the overpotential for oxygen evolution reaction. Ni foam-supported Fe-doped β-Ni(OH) 2 nanosheets achieve an overpotential of 219 mV at the geometric current density of 10 mA cm -2 . To our knowledge, this is the best value reported for Ni- or Fe hydroxide-based OER catalysts. In addition, the catalyst yields a current density of 6.25 mA cm -2 at the overpotential of 300 mV when it is normalized to the electrochemical surface area of the catalyst. This intrinsic catalytic activity is also better than the values reported for most state-of-the-art OER catalysts at the same overpotential.

We report a rare example of a sulfonate-based metal–organic framework (MOF) possessing a prototypical primitive-cubic topology, constructed with Jahn–Teller distorted Cu(II) centers and a mixed-linker (organosulfonate and N-donor) system. The inherent highly polar, permanent porosity contributes to the highest reported CO2 sorption properties to date among organosulfonate-based MOFs, outperforming the benchmark carboxylate MOF counterpart. Importantly, density functional theory calculations confirm that the CO2–sulfonate interaction plays an important role in CO2 capture. Indeed, the hydrothermal product demonstrates high robustness over a wide pH range as well as aqueous boiling conditions, overcoming the moisture sensitivity of conventional Cu2 paddlewheel-based MOFs. In addition, bulk synthesis of this material has been successfully achieved on a gram scale (>1 g) in a single batch with a high yield. Combining the high CO2 affinity and a robust nature, this sulfonate porous material is also an efficien...

We report a regenerable adsorbent for the removal of refractory organosulfur compounds from fossil fuels. The material is composed of well-dispersed silver nanoparticles confined within the mesochannels of aluminum-doped MCM-41 nanoparticles. With an average initial desulfurization capacity of 15 mg S·g–1, 79% desulfurization capacity is retained after six cycles for the removal of dibenzothiophene from n-decane. The addition of intraframework aluminum to form a mesoporous aluminosilicate nanoparticle (MASN) aids in the retention and dispersion of silver ions within the mesochannels (Ag-MASN). The nanoparticles are subsequently reduced by glow discharge plasma treatment in argon (PT-Ag-MASN). The size dispersion, surface area, and structural integrity were characterized by scanning electron microscopy, annular dark-field scanning transmission electron microscopy (ADF-STEM), nitrogen adsorption analysis (BET), and powder X-ray diffraction. Silver nanoparticle formation within the mesochannels of MASN was c...

The surprising discovery of salutary effects of low doses of carbon monoxide (CO) in mammalian physiology has raised intense research interest in CO delivery to biological targets under controlled conditions. In recent attempts, photoactive metal carbonyl complexes (photoCORMs) have been employed to trigger CO release at the target sites. In this work, a designed photoCORM namely, fac-[Re(CO)3(pbt) (PPh3)](CF3SO3) (1, pbt =2-(2-pyridyl)benzothiazole) has been synthesized and characterized by spectroscopic methods and crystallography. This photoCORM not only releases CO upon illumination with low-power UV light (305 nm, 5 mW cm–2) but also exhibits a “turn-off” of its orange luminescence (λem = 605 nm) upon release of one CO ligand. The latter property provides a convenient way to track the CO release event. The photoCORM 1 has been entrapped within the pores of the narrow channels of 100 nm mesoporous Al-MCM-41 nanoparticles and the loaded {Re-CO}@Al-MCM-41 MSNs have been characterized by powder X-ray dif...

We present a new method in the synthesis of metal–organic framework (MOF) thin films using zinc oxide nanowires as the substrate. This facile method involves growing zinc oxide nanowires on a substrate (glass, transparent conducting oxide glass, Si wafer), followed by immersing the nanowire substrate in an iso-reticular metal–organic framework (IRMOF) precursor solution. The resulting 25 μm thick film is highly crystalline and covers the entire substrate. Growth of the IRMOF on the nanowire substrate allows for the film to be used in potential applications in sensing, membranes, photovoltaics, catalysis, and gas storage. We have also successfully used microwaves to rapidly produce these films with comparable film quality to our original method.

Desulfurized JP-8 fuel is of great interest for use as the hydrogen feedstock of fuel cells. The refractory aromatic sulfur species present, however, are particularly challenging to remove through traditional methods. We report the first use of mesoporous silica nanoparticles (MSN) for desulfurization and the material displays a four-fold greater performance towards JP-8 fuel over previous sorbents. The bulk form of mesoporous silica shows three-fold greater level of desulfurization. Silver-impregnated nanoparticle and bulk MCM-41 were found to have saturation adsorption capacities of 32.6 mgS g−1 and 25.4 mgS g−1, respectively. MSN display a high capacity for the notoriously difficult to remove 4,6-dimethyldibenzothiophene along with a two-fold improvement in breakthrough capacity over previously published materials, of 0.98 mgS g−1 at 10 ppmwS.

We have successfully synthesized a rare example of an open framework nickel oxide with succinate capping the channels. A honeycomb-like layer of 14-membered rings centered in the (11) plane are connected by vertex-sharing NiO6 octahedra and water resides in the channels. The structure is only the second example of an extended inorganic–organic hybrid material containing 3-D Ni–O–Ni connectivity and was structurally characterized by single-crystal and powder X-ray diffraction. The material displays excellent chemical stability in aqueous solution from pH ∼ 1 to 13 and thermal stability to ∼375 °C as evidenced by thermogravimetric analysis coupled mass spectroscopy. The Ni2+ ions order ferromagnetically below Tc = 5.1 K and anisotropic exchange interactions lead to a field-induced metamagnetic transition and spin-glass-like dependence on cooling conditions in magnetic field.

A three-dimensional Bi(III) based metal–organic framework was synthesized under hydrothermal conditions using the multidentate organic linker 3,5-pyridinedicarboxylate. Bismuth oxide 3,5-pyridinedicarboxylate, Bi2O2[NC5H3(CO2)2], contains embedded 1-D cationic bismuth oxide chains that propagate along the crystallographic c-axis. The oxygens of the Bi2O2 core are three-coordinate and bond strongly to the Bi atoms. Thermogravimetric analysis shows that the material possesses high thermal stability up ca. 400 °C before decomposing to phase-pure Bi2O3 at 800 °C. The structure, crystallinity, morphology and properties of the material are discussed.

We have discovered a metal−organic framework containing cationic inorganic layers. The metal fluoride−organodisulfonate structure, Pb2F2[C2H4(SO3)2], was synthesized hydrothermally. The lead fluoride cationic layers are covalently connected by 1,2-ethanedisulfonate chains oriented perpendicular to the layers. The material is thermally stable to ca. 325 °C, above which the material collapses to phase-pure α-PbF2. This material is a rare example of the use of organosulfonates as organic linker and the first metal−organic framework to contain lead fluoride connectivity. The existence of extended cationic inorganic moieties embedded within a metal−organic framework material further diversifies the possible structure types of this rapidly growing class of materials.

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.

The first example of a unidimensional zirconium hydroxide fluoride was synthesized under mild solvothermal treatment and characterized by X-ray diffraction and thermal techniques. Monoprotonated ethylenediamine cations reside between the anionic chains. Crystal data for this material are as follows: [C2N2H9][Zr(OH)2F3], M=243.35, orthorhombic, space group Pca21, a = 6.8 0 1 6 ( 1 3 ) , b = 6.1 3 9 3 ( 1 2 ) , c = 1 4.8 6 7 ( 3 ) A , V = 6 2 0.8 ( 2 ) A 3 , T = 2 9 4 ( 2 ) K , Z = 4 , D c = 2.6 0 4 g cm - 3 , μ(Mo-Kα)=1.777 mm−1, λ = 0.7 1 0 7 3 A . The material transforms to an unknown layered material at ∼175 °C, a common occurrence for 1D structures where the chains are arranged in hydrogen-bonded layers and separated by interlayer organoammoniums. Collapse to the known condensed mineral phase Zr(FO)2.7 occurs at ca. 275 °C before finally transforming to the baddeleyite form of ZrO2 at ca. 460 °C.

We report the hydrothermal synthesis and characterization of a layered cobalt phenylphosphonate. Unlike most metal phosphonates reported to date, the structure was solved by single crystal X-ray diffraction (SC-XRD). Co(ii) centres are hexa-coordinated by oxygen and the octahedra corner-share into a layer. The layers are capped by phenylphosphonate groups, where the phenyl groups define a hydrophobic bilayer region. The material was also characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and SQUID (superconducting quantum interference device) magnetometry. The material undergoes an antiferromagnetic transition at a relatively low Néel temperature of 4.0 K, while the Curie-Weiss temperature of -76.5 K reflects the low-dimensionality of the magnetic structure. The effective magnetic moment of 5.01 micro(B) per Co(2+) verifies a high-spin configuration and an octahedral coordination of the metal centres. This layered material was correctly predicted in the literature from powder data, adds to the structural diversity of the cobalt phosphonates, and may be useful as an intercalation or exfoliation compound.

This paper demonstrates the use of poly(dimethylsiloxane) (PDMS), polyurethane (PU), epoxy, and poly(methyl methacrylate) (PMMA) as mandrils to fabricate metallic heat exchangers having 300-700 /spl mu/m internal channels. The mandrils were prepared using two soft lithographic techniques-replica molding and microembossing. To fabricate the heat exchangers, the polymeric mandrils were coated with a thin layer of metal by thermal evaporation or sputtering; this layer acted as the cathode for electrodeposition of a shell of nickel or copper that was 100 /spl mu/m thick. The polymers were removed by burning them out at 400/spl deg/C in air, or by dissolving them with a tetrahydrofuran solution of tetrabutylammonium fluoride. Studies of heat dissipation showed that the nickel heat exchangers with features that range in size from 150-750 /spl mu/m have thermal resistances ranging from 0.07 to 0.12/spl deg//sup -2/C W/sup -1/ cm at flow rates of water of /spl sim/20 L h/sup -1/ and pressures of 8.6-83/spl times/10/sup 3/ N m/sup -2/.

The synthesis and characterization of two novel aluminophosphate materials, obtained from the same nonaqueous tetraethylene glycol−cyclopentylamine system, is reported. The first material, [Al3P5O20H]5-·5[C5H9NH3+], denoted UT-2, has a 1-D chain structure with a P:Al ratio of 5:3, rather than 1:1 as found in the aluminophosphate AlPO4-n molecular sieves. The UT-2 chains are hydrogen-bonded together by terminal phosphate groups and organized into a layered structure. The second material, [Al2P3O12H]2-·2[C5H9NH3+], denoted UT-3, has a 2-D layer structure with a P:Al ratio of 3:2. Both materials have bilayers of charge-balancing cyclopentylammonium cations interdisposed between anionic aluminophosphate sheets. Variable-temperature in situ PXRD establishes a clean solid-state structural transformation, at 200 °C, of UT-2 to UT-3. The discovery of this chain-to-layer conversion suggests a new paradigm for the templated assembly of 1-D chain, 2-D layer, and 3-D open-framework aluminophosphates.

Two metal-organic frameworks containing barium were synthesized hydrothermally and investigated for their catalytic properties. Ba(2)F(2)[O(3)SC(2)H(4)SO(3)] has barium fluoride layers linked by organic 1,2-ethanedisulfonate molecules. Ba[O(3)SC(2)H(4)SO(3)] has discrete barium centers arranged in layers and connected covalently by ethanedisulfonate bridges. Thermogravimetric analysis showed that Ba(2)F(2)[O(3)SC(2)H(4)SO(3)] is stable to ca. 325 °C and Ba[O(3)SC(2)H(4)SO(3)] to ca. 375 °C. These materials expand the metal-organic frameworks available for group II metals bound to organodisulfonate linkers and are potentially useful for a range of heterogeneous acid catalysis reactions.

We have successfully synthesized three cadmium-based metal–organic frameworks by utilizing two separate organic linkers to direct the structure. The first material is a three-dimensional neutral framework based on 2D cadmium ethanedisulfonate layers pillared by a 4,4′-bipyridine linker. The other two materials are 3D cationic frameworks and are the first with propanedisulfonate and butanedisulfonate as extraframework charge balancing anions. Both structures occupy a high symmetry hexagonal crystal system where Cd-bipy chains are arranged into three crystallographically distinct layers that stack spirally along [001]. The framework is stabilized by alkanesulfonate anions that are electrostatically and hydrogen bonded to the framework. Each material was characterized by single-crystal and powder X-ray diffraction. The thermal and luminescent properties were also investigated by thermogravimetric analysis and photoluminescence spectroscopy, respectively. All three materials exhibit high thermal stability to above 300 °C and efficient blue emissive photoluminescence centered at 425 nm to 450 nm upon 350 nm excitation.

We have discovered a facile and inexpensive approach to fabricate "nanospider" TiO(2) thin films with not only an amazing morphology but highly efficient water splitting to produce hydrogen. Our method employs benzene-swollen poly(ethylene glycol) as a sacrificial organic polymer to template the semiconductor thin film. The synthesized TiO(2) thin films are highly crystalline with optimized particle and channel size to enhance the liquid-semiconductor junction interaction. This enhanced contact area leads to more than twice the water splitting performance than conventional P25 thin films. In addition, the nanospider thin films also outperform P25 films in the photodegradation of toxic organics.

We have developed a simple, low-cost process to fabricate free-standing porous metal oxide monoliths. Various swollen polymers and hydrogels possessing an open network structure are infiltrated with pure liquid metal alkoxide. Hydrolysis followed by chemical or thermal degradation of the polymer leads to bulk porous monoliths, TiO2 and SiO2 as initial examples. The titania solids were subsequently employed as photocatalysts under UV light and monitored for adsorption. The materials show efficient reusable photocatalytic ability as compared to pure-phase nanoparticle titanium oxide.

Ceramic coatings can be effectively used as a surface protective layer for silicon-based devices due to their inertness and good mechanical properties. One challenge is to avoid the weaknesses that ceramic coatings inherently possess, i.e., low strain tolerance, brittleness, high temperature required to process the film, and difficulty to produce a uniform, dense layer. Therefore, in an attempt to process strain-tolerant ceramic coatings at low temperatures, we develop an aqueous solution precursor processing route. Nanometer scale organic coatings, fabricated by self-assembly processes on the silicon, are used as a ‘template’ to aid the subsequent deposition of hard ceramic coatings (ZrO2 ). The ceramic coatings are deposited by spin coating. The organic self-assembled monolayer (SAM) coating provides temporary strain tolerance for the overlying hard coating upon mechanical and thermomechanical stresses before being decomposed at high temperatures. Molecular level understanding of the coating microstructure and micromechanics involved in the coating processes is systematically approached via experimental tools such as AFM and nanoindenter, as well as numerical simulation.Copyright © 2003 by ASME

Our research involves the solvothermal synthesis and characterization of new 3D open-framework and low dimensional inorganic materials. We focus on heavier group 14 elements to prepare structures that are analogous to aluminosilicate zeolites, but the main emphasis is to obtain cationic materials, a feat not possible with silicon oxides. We have successfully synthesized a series of novel compounds with Pb as building block: a cationic layered lead fluoride material (BING-5, Pb3F5NO3); a neutral, layered lead phenylphosphonate pyridine (BING-6); and a layered lead metamethylphenyl-phosphonate (BING-9). A molecular solid, tetrafluorodipyridine-germanium (BING-10) was also obtained. These structures are characterized by a variety of solid state techniques, including: powder X-Ray diffraction (PXRD), thermogravimetric analysis (TGA), UV-Vis spectroscopy and NMR. Our BING-5 material can exchange its interlayer NO3- for a variety of other anions. It is also stable to 450°C, which is far superior to organic resins that are still the standard for anion-exchange.

A variety of titania microstructures have been synthesized using a swollen polymer matrix of polydimethylsiloxane (PDMS). The shapes and structures grown to date include spheres, ‘bowls’, ‘nets’ and ‘brain coral’ matrices. The PDMS polymer network can be swollen by one of a variety of organic solvents. These solvents create internal voids or spaces within the PDMS, of particular volume. These spaces can then be filled with metal alkoxide liquid. The metal alkoxide is then polymerized to form metal oxides, in a shape templated by the swollen PDMS polymer. The resultant product is a composite of metal oxide within a polymer. Some of the shapes can be removed mechanically or chemically. Methods of characterization include scanning electron microscopy (SEM) and optical microscopy. Potential applications of the shaped titania include catalysts, fillers, capsules, and chemical separators. The synthesis and characterization of these compounds will be discussed.

We report the synthetic conditions, physical properties and potential applications of late group 14 metal (Sn) 0D, 1D, 2D and 3D extended materials. The structures are primarily neutral chain and anionic layered compounds. The latter are charge-balanced by ammonium cations, as in and BING-7 [Sn(C2O4)F-] [NH4+] and BING-8 [Sn(PO4H)F-] [NH4+]. The neutral layered compound and chain compounds BING-1 [Na4Sn4(C2O4)F6], BING-2 [KSn(C2O4)F] and BING-4 [Sn(C2O4)(C5H5N)] have also been synthesized solvothermally. Thermogravimetric analysis (TGA) under nitrogen and in-situ variable temperature X-ray diffraction show that the materials decompose in the 200°C to 300°C range to more stable phases. Nuclear magnetic resonance (NMR) was used to monitor the ion-exchange properties of some of the materials. The intercalation properties of these materials are still being investigated.

A series of well-ordered, extended mesostructures has been generated from hexagonal polyurethane rods (15x3.2 mm) by self-assembly using capillary forces. The surface of one or more sides of the rods was rendered hydrophilic by exposure to an oxygen plasma. This modification determined the pattern of hydrophobic and hydrophilic faces; the hydrophobic sides were coated with a thin film of a hydrophobic lubricant. Agitation of the rods in an approximately isodense aqueous environment resulted in their self-assembly, in a process reflecting the action of capillary forces, into an array whose structure depends on the pattern of hydrophobic sides; capillarity also aligned the ends of the rods. We also carried out experiments in reaction chambers that restricted the motion of the rods; this restriction served to increase the size and regularity of the assemblies. Copyright 2000 Academic Press.

A photoactive manganese carbonyl complex namely, fac-[Mn(pqa)(CO)3]ClO4 (abbreviated as {Mn–CO}, pqa = (2-pyridylmethyl)(2-quinolylmethyl)amine) has been incorporated in the pores of 60 nm mesoporous Al-MCM-41 nanoparticles. Strong electrostatic interactions with the negatively charged walls of the aluminosilicate host entrap the cationic carbonyl complex in the resulting material {Mn–CO}@Al-MCM-41 which has been characterized by various physical techniques and chemical analysis. The sample morphology and microstructure of the material have been established by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results of powder X-ray diffraction (PXRD) data and the SEM-EDX elemental maps of Si, O, Al and Mn confirm that the carbonyl complex is within the pores of the nanoparticles. The 2% manganese content of {Mn–CO}@Al-MCM-41, determined by acid digestion followed by inductively coupled plasma-optical emission spectroscopy (ICP-OES), indicates efficient loading of the carbonyl complex in the nanoparticles. In biological buffer solutions, less than 2% leaching of {Mn–CO} from the nanoparticles was noted within a period of 24 h. When exposed to a broadband visible light source (λ > 350 nm), {Mn–CO}@Al-MCM-41 rapidly releases CO, as confirmed by the reduced myoglobin assay. The utility of light-induced CO delivery by {Mn–CO}@Al-MCM-41 has been established by its capacity to relax rat aorta muscle rings in tissue bath experiments.

We report a rapid and inexpensive method to fabricate double-layer porous TiO2 electrodes for quasisolid dye-sensitized solar cells. Polymethylmethacrylate mixed with titanium alkoxide in methyl ethyl ketone was used as template precursor. Thermal removal of the polymer at 500°C leads to mesoporous double-layer TiO2 thin films of nanocrystalline anatase. The cells show a high open-circuit voltage of ∼1.18V and overall photoelectric conversion efficiency of 2.05% under an illumination of one sun (AM1.5 global, 100mW∕cm2).

The authors report the contact printing of a Au∕Co double layer (total thickness ∼20–40nm) onto a self-assembled monolayer surface to form molecular junctions under ambient conditions. The feature size ranges from 50×50μm2to2×2mm2. Grazing incident x-ray diffraction of the multilayer junction shows all expected Au peaks, while elemental Co was confirmed by energy dispersive spectroscopy. Film thickness, roughness, and density were characterized by x-ray reflectivity. I-V measurements show a prominent hysteresis, likely associated with charge trapping at the metal-organic interface, not an intrinsic feature of alkanedithiol molecules.

The synthesis of aluminophosphates from a nonaqueous tetraethylene glycol–cyclohexylamine medium yields two new layered materials that have been solved by single-crystal X-ray diffraction.