Creation of a Highly Active Small Cu-Based Catalyst Derived from Copper Aluminium Layered Double Hydroxide Supported on α-Al O for Acceptorless Alcohol Dehydrogenation.

A highly dispersed carbonate-intercalated Cu -Al layered double hydroxide (CuAl LDH) was created on an unreactive α-Al O surface (CuAl LDH@α-Al O ) via a simple coprecipitation method of Cu and Al under alkaline conditions in the presence of α-Al O . A highly reducible CuO nanoparticles was generated, accompanied by the formation of CuAl O on the surface of α-Al O (CuAlO@α-Al O ) after calcination at 1073 K in air, as confirmed by powder X-ray diffraction (XRD) and Cu K-edge X-ray absorption near edge structure (XANES). The structural changes during the progressive heating process were monitored by using in-situ temperature-programmed synchrotron XRD (tp-SXRD).

Ultra-sensitive detection of pyridine in water using zinc porphyrin incorporated in a transparent hydrophobic film.

In this study, we investigated the axial coordination reaction between pyridine and zinc meso-tetra(4-sulfonatophenyl)porphyrin (ZnTPPS) incorporated in a transparent layered double hydroxide (LDH) film modified with 1-decanesulfonate (C10S) in an aqueous solution. The apparent equilibrium constant ([Formula: see text]) of the axial coordination reaction between pyridine and ZnTPPS incorporated in the transparent ZnTPPS/C10S/LDH film was approximately 260 times that of the corresponding reaction in an aqueous solution. The hydrophobisation of the LDH interlayer space by C10S, which led to the elimination of water molecules surrounding ZnTPPS and enabled the accumulation of pyridine molecules, was responsible for such a significant increase in the apparent [Formula: see text] value.

Important Roles of Water Clusters Confined in a Nanospace as Revealed by a Synchrotron X-ray Diffraction Study.

States of water molecules confined in a nanospace designed by montmorillonite (negatively charged silicate layer) and charge compensating benzylammonium were investigated. Caffeine was used as a probe because of its compatibility for the fine structure of the interlayer water. Powder synchrotron radiation X-ray diffraction (SXRD) and adsorption isotherms of the water vapor revealed a metastable structure of bimolecular water layers (2WLs) in the interlayer space.

Photoluminescence Gas Sensing by Fluorescein-Dye Anions/1-Butanesulfonate/Layered Double Hydroxide Hybrid Materials under Humid Environment Conditions.

In this study, we investigated the photoluminous spectroscopic behavior of hybrid powder incorporating both anionic fluorescein dye (AFD) and 1-butanesulfonate (C4S) with layered double hydroxide (LDH) in the presence of NH or NO gas under various relative humidity conditions. In the presence of NH gas, drastic photoluminescence enhancement from the LDH/AFD/C4S hybrid was observed at relative humidity (RH) ≥ 40% when the NH reached a certain concentration. Meanwhile, the LDH/AFD/C4S hybrid was exposed to NO gas at various relative humidity conditions, and the following behavior was observed: At RH ≥ 60%, the photoluminescence (PL) intensity from the hybrid gradually decreased as NO concentration increased.

Photocatalytic Hydrogen Evolution over Exfoliated Rh-Doped Titanate Nanosheets.

Various amounts of Rh-doped titanate nanosheets (TiNS:Rh(), where is doped amount) were prepared to develop a new nanostructured photocatalyst based on metal oxide compounds that can split water to produce H under sunlight. TiNS:Rh() was obtained by acid exchange, intercalation, and exfoliation of Rh-doped layered sodium titanate compound (NaTi Rh O). A new energy gap was found in the diffuse reflection spectrum of the TiNS:Rh() colloidal suspension solution; this new energy gap corresponds to electrons in the 4d level of Rh or Rh, which are doped in the Ti site.

Why Do Carbonate Anions Have Extremely High Stability in the Interlayer Space of Layered Double Hydroxides? Case Study of Layered Double Hydroxide Consisting of Mg and Al (Mg/Al = 2).

Layered double hydroxides (LDHs) are promising compounds in a wide range of fields. However, exchange of CO anions with other anions is necessary, because the CO anions are strongly affixed in the LDH interlayer space. To elucidate the reason for the extremely high stability of CO anions intercalated in LDHs, we investigated in detail the chemical states of CO anions and hydrated water molecules in the LDH interlayer space by synchrotron radiation X-ray diffraction, solid-state NMR spectroscopy, and Raman spectroscopy.

Synthesis, photodynamic activities, and cytotoxicity of new water-soluble cationic gallium(III) and zinc(II) phthalocyanines.

The cationic Ga(III) and Zn(II) phthalocyanines carrying N-methyl-pyridinium groups at eight peripheral β-positionshave been synthesized. These complexes are highly soluble in dimethyl sulfoxide (DMSO) and moderately soluble in water and phosphate buffered saline (PBS); both Ga(III)Cl and Zn(II) complexes have shown no aggregation in water up to 1.2 × 10 and 1.

Optical Humidity Sensing Using Transparent Hybrid Film Composed of Cationic Magnesium Porphyrin and Clay Mineral.

A transparent hybrid film composed of cationic magnesium porphyrin and clay mineral was developed, and its chromic behavior depending on relative humidity (RH) was investigated. The hybrid film was obtained via intercalation of magnesium porphyrin into clay film; magnesium porphyrin was intercalated into the interlayer spaces of the clay mineral without aggregation. The absorption spectra of the hybrid film showed red shifts compared to the aqueous solution of magnesium porphyrin because of the π-conjugated system extension with coplanarization of the meso-substituted pyridinium group and porphyrin ring.

Preparation of Stable Silver Nanoparticles Having Wide Red-To-Near-Infrared Extinction.

The synthesis of silver nanoparticles (AgNPs) within the interlayer space of transparent layered titania nanosheet (TNS) films is investigated. A considerable number of silver ions (≈70% against the cation exchange capacity of the TNS) are intercalated in the TNS films using methyl-viologen-containing TNSs as a precursor. The silver ion (Ag)-containing TNS films are treated with aqueous sodium tetrahydroborate (NaBH), resulting in a gradual color change to bright blue.

Photoluminescence by Intercalation of a Fluorescent β-Diketone Dye into a Layered Silicate.

A β-diketone dye was packed into the two-dimensional nanospace of a synthetic smectite (Sumecton SA), which is a cation-exchangeable layered silicate, to induce strong emission owing to molecular packing of the dye. An emissive dye, 1-(4-methoxyphenyl)-3-(4-pyridyl)-1,3-propandione, was prepared through a Claisen condensation reaction; the dye exhibited aggregation-induced emission, which is enhanced emission owing to clustering of molecules to form aggregates in poor solvents or in the solid state. The dye was nonemissive in solution.

Dielectric Mismatch Mediates Carrier Mobility in Organic-Intercalated Layered TiS2.

The dielectric constant is a key parameter that determines both optical and electronic properties of materials. It is desirable to tune electronic properties though dielectric engineering approach. Here, we present a systematic approach to tune carrier mobilities of hybrid inorganic/organic materials where layered two-dimensional transition-metal dichalcogenide TiS2 is electrochemically intercalated with polar organic molecules.

Rapid exchange between atmospheric CO2 and carbonate anion intercalated within magnesium rich layered double hydroxide.

The carbon cycle, by which carbon atoms circulate between atmosphere, oceans, lithosphere, and the biosphere of Earth, is a current hot research topic. The carbon cycle occurring in the lithosphere (e.g.

Intercalation of a surfactant with a long polyfluoroalkyl chain into a clay mineral: unique orientation of polyfluoroalkyl groups in clay layers.

Eight novel polyfluorinated surfactants (C(n)F(2n+1)CONH(CH2)2 N(+)(CH3)2C16H33 Br(-); abbreviated as CnF-S, where n = 1, 2, 3, 4, 5, 6, 8, 10) were synthesized and their intercalation into cation-exchangeable clay was investigated. All of the polyfluorinated surfactants intercalated in amounts exceeding the cation exchange capacity (CEC) of the clay. The C4F-S and C5F-S surfactants exhibited intercalation up to 480% of the CEC as a saturated adsorption limit.

Behavior of chiral induction from polysilsesquioxanes bearing chiral and ammonium groups to anionic pyrene derivatives.

The behavior of chiral induction from ladder-like polysilsesquioxanes (R60- and S60-PSQs) bearing chiral and ammonium side-chain groups (compositional ratio = ca. 60:40) to the anionic pyrene derivative, 1,3,6,8-pyrenetetrasulfonic acid tetrasodium salt (PTSNa4), was investigated. The circular dichroism (CD) spectra of PTSNa4/(R60- and S60-PSQs) mixtures in methanol exhibited reverse peaks at 230-250, 280-290, and 310-370 nm, which were assigned to PTSNa4 and indicated that the achiral PTSNa4 molecule had chirality induced from the chiral PSQs.

Nitrate-ion-selective exchange ability of layered double hydroxide consisting of MgII and FeIII.

In this study, layered double hydroxide (LDH) consisting of Mg(II) and Fe(III) (Mg/Fe-LDH) was synthesized by using a combination of coprecipitation with hydrothermal aging, and its anion-exchange properties were investigated. Through various analyses, the chemical formula of the proposed Mg/Fe-LDH was determined to be [Mg(0.76)Fe(0.

Development of an eco-friendly material recycling process for spent lead glass using a mechanochemical process and Na2EDTA reagent.

To develop a novel nonheating method with lower energy consumption and higher efficiency for recovering both lead and SiO2 glass matrix from spent lead-glass powder, we attempted to treat the spent lead glass by the mechanochemical method using the metal chelate reagent, sodium ethylenediaminetetraacetate (Na2EDTA). As a result of the wet ball-milling treatment of spent lead-glass powder sealed in a polypropylene bottle with zirconia balls, Na2EDTA, and water at room temperature, we found that more than 99 mass % of lead contained in the spentlead-glass powder was extracted as a lead-EDTA species from the solid silica glass network matrix. This separation phenomenon was accelerated by the enlargement of the solid-liquid interface area due to ball-milling atomization and by the high stability constant of lead-EDTA.

Arsenic recovery from water containing arsenite and arsenate ions by hydrothermal mineralization.

Recovery of arsenic as precipitate of natural mineral from model wastewater containing various initial concentrations and oxidation states of inorganic arsenic oxoanions was investigated by hydrothermal mineralization treatment. The treatment is an earth-mimetic method to produce natural minerals by hydrothermal treatment using Ca(OH)2 as a mineralizer. The treatment of model wastewater containing arsenate ion or mixed aqueous solution of arsenate and arsenite ions by using Ca(OH)2 mineralizer and H2O2 oxidizer was found to precipitate arsenate apatite which is a natural mineral containing high concentration of arsenic.

Zinc chelation and photofluorochromic behavior of spironaphthoxazine intercalated into hydrophobically modified montmorillonite.

Spironaphthoxazine (SNO) and Zn2+ were intercalated into montmorillonite interlayers hydrophobically modified by the alkyltrimethylammonium cation during UV light irradiation. The fluorescence spectra of the montmorillonite composites were observed to vary with an increase in the UV and visible light irradiation times. These composites exhibited two types of fluorescence emissions: F1, which originates from a new species, Xs, which is different from SNO (ring-closed form) and merocyanine (MC; ring-open form), and F2, which originates from the MC-Zn complex.

Electrooptics of beta-FeOOH particle in aqueous media 2. Field-strength dependence of decay and steady-state birefringence, and the hydrodynamic and electrooptic properties.

Steady-state and decay birefringence, expressed in terms of the optical phase retardation per cell length delta/d, was measured on beta-FeOOH in aqueous ionic media at 633 nm and at 25 degrees C by an electric square-pulse technique over a wide range of field strength E to ca. 6 kV/cm. The field-strength dependence of both delta/d and field-free rotational relaxation time tau was determined at the sample concentrations between 0.

Lead recovery from PbZrO3 using wet ball-mill technique and hydrothermal synthesis of alpha-zirconium phosphate from wastewater for resource recovery.

Lead recovery from lead zirconate (PbZrO(3)) ceramics was investigated using a wet ball-mill treatment in H(2)SO(4) aqueous solution. Subsequently crystalline alpha-zirconium phosphate (alpha-Zr(HPO(4))(2).H(2)O) was synthesized using a hydrothermal technique in order for the resource recovery of zirconium in the wastewater after the wet ball-mill treatment.

Precipitation recovery of boron from wastewater by hydrothermal mineralization.

It is well known that boric acid exhibits various toxic effects on plant, animal and human beings even at very low concentrations. Thus, the development of boron-removal technique from wastewater has been intensively investigated. In this study, a new hydrothermal treatment technique was developed to recover boron as recyclable precipitate Ca(2)B(2)O(5).

Luminescence properties of rhodamine 6G intercalated in surfactant/clay hybrid thin solid films.

To develop the solid-state laser oscillator based on laser dye compounds, the incorporation of rhodamine 6G (R6G, a laser dye) in cetyltrimethylammonium (CTA+) cationic surfactant/montmorillonite clay hybrid (HpC) thin solid films was investigated. The R6G/HpC samples were prepared by immersing the HpC films into a R6G aqueous solution with various concentration. X-ray diffraction patterns of the films of HpC, measured before and after the intercalation of R6G, proved the coexistence of both the dye and surfactant in clay interlayer spaces.

Effect of layer charge density on orientation and aggregation of a cationic laser dye incorporated in the interlayer space of montmorillonites.

Effect of layer charge density of clay on the orientation and aggregation state of a laser dye, oxazine 4, in dye/clay complexes was investigated using a series of layer-charge-controlled montmorillonites as host materials. By the combination of polarized UV-vis spectroscopy and powder X-ray diffraction methods, it was revealed that the higher layer charge caused the formation of higher-order H-aggregates with the molecular axis nearly perpendicular to the silicate layer, and that the basal spacing was mostly governed by the degree of dye aggregation.