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Morphological control of C60 fullerene using liquefied porphyrins (1 and 2) as the host matrices was explored. Slow evaporation of the solvent of the equimolar mixture of porphyrin and C60 in toluene afforded the porphyrin/C60 composite with a 3:1 molar ratio. The stoichiometric binding behaviors suggest that specific porphyrin-C60 interactions operate the formation of the porphyrin/C60 composites, as corroborated by spectroscopic and thermal properties, and glazing-incidence wide-angle X-ray diffraction. Under the bulk conditions, the conventional thermodynamic advantage of multiple binding cooperativity for molecular recognition is unlikely to explain the stoichiometric binding behaviors. Instead, we propose a size-matching effect on the porphyrin-C60 interaction in the bulk porphyrin matrices, i.e., "supramolecular solvation". The glassy nature of the porphyrin matrices was transmitted to C60 through the specific interaction, and the porphyrin/C60 composites adopted glassy states at room temperature.

Near-infrared (NIR) light irradiation induced the transformation of polypyrrole (PPy) to nitrogen-containing carbon (NCC) material due to its light-to-heat photothermal property. The temperature of the PPy increased over 700 °C within a few seconds by the NIR laser irradiation, and elemental microanalysis confirmed the decreases of hydrogen and chloride contents and increases of carbon and nitrogen contents. Monodispersed polystyrene (PS)-core/PPy shell particles (PS/PPy particles) synthesized by aqueous chemical oxidative seeded polymerization were utilized as a precursor toward monodispersed NCC capsules. When the NIR laser was irradiated to the PS/PPy particles, the temperature rose to approximately 300 °C and smoke was generated, indicating that the PS component forming the core was thermally decomposed and vaporized. Scanning electron microscopy studies revealed the successful formation of spherical and highly monodispersed capsules, and Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy studies confirmed the capsules consisted of NCC materials. Furthermore, sunlight was also demonstrated to work as a light source to fabricate NCC capsules. The size and thickness of the capsules can be controlled between 1 and 80 μm and 146 and 231 nm, respectively, by tuning the size of the original PS/PPy particles and PPy shell thickness.

Morphological control of C

We report on the transformation of dichloromethane to low-chlorine carbon nanoparticles by the exposure of aqueous dichloromethane solution and/or dichloromethane/water biphasic solution to femtosecond laser pulses. The pH of either solution immediately decreased due to the reduction of dichloromethane by hydrated electrons. The time evolution of transmittance revealed that particle formation was suppressed when the initial pH was low because protons scavenge hydrated electrons. The size and morphology of nanoparticles was independent of the initial pH and the reaction solution used. The analysis of the elemental composition of carbon particles showed that the Cl/C atomic ratio was, independent on the initial pH values, greatly reduced to 0.06. We propose that the violent destruction of dichloromethane and elimination of chlorine atoms not only as Cl − but also Cl 2 excludes chlorine atoms from the carbon network construction processes toward the formation of carbon nanoparticles.

有機溶媒(ヘキサフロロベンゼン)にフェムト秒レーザーを照射することで、フッ素原子を含んだ炭素ナノ粒子(約50nm)を極めて簡便に合成することに成功しました。通常のフッ素導入法とは異なり、本手法では加熱の必要がなく室温で実施可能です。また、反応溶液を不活性ガスで保護するなどの特別な処置は不要であり、空気が存在しても反応が起こります。さらに、水が過剰に存在する条件でも粒子が生成されます。……(参照 LINK1), We report on the preparation and characterization of fluorine-doped hydrophilic carbon nanoparticles by the exposure of hexafluorobenzene or a water/hexafluorobenzene bilayer solution to femtosecond laser pulses. Uniform atom distributions were achieved not only on the particle surface but also inside the particles....

The space integration of the lithiation of aryl halides, the borylation of aryllithiums, and Suzuki&ndash, Miyaura coupling using a Pd catalyst supported by a polymer monolith flow reactor without using an intentionally added base was achieved. To scale up the process, a series connection of the monolith Pd reactor was examined. To suppress the increase in the pressure drop caused by the series connection, a monolith reactor having larger pore sizes was developed by varying the temperature of the monolith preparation. The monolithic Pd reactor having larger pore sizes enabled Suzuki&ndash, Miyaura coupling at a higher flow rate because of a lower pressure drop and, therefore, an increase in productivity. The present study indicates that series connection of the reactors with a higher flow rate serves as a good method for increasing the productivity without decreasing the yields.

Organic-inorganic hybrid materials by dispersing inorganic nanoparticles in organic polymers are expected as functional substances with synergistic properties. Recently, high refractive index thin films are most important materials for optical devices such as flat panel display, touch panel, etc. These hybrids with dispersion of surface-modified zirconia nanoparticles can provide the controlled refractive index materials. It is necessary for the preparation of transparent hybrid materials to disperse zirconia nanoparticles in organic solvent or polymer solution by a beads mill process. Effective surface modifications of zirconia nanoparticles were successfully developed by two treatments of (1) with silane coupling agent and isocyanate compound and (2) with dual-site silane coupling agent. These dispersions can be applied to prepare the high refractive index thin films.

Integration of the preparation of arylboronic esters via aryllithiums and Suzuki–Miyaura coupling using monolithic Pd catalyst without an intentionally added base was achieved. A continuous operation has been done successfully for over 21 hours.

We synthesized hydrophilic and hydrophobic carbon nanoparticles (CNPs) by femtosecond laser (0.8 µm, 40 fs) irradiation of the water layer of an aerated benzene/water (B/W) bilayer solution. Focusi...

The surfaces of polyethylene naphthalate and polyethylene terephthalate films were modified by plasma treatment, layer-by-layer (LbL) assembly of polyelectrolyte multilayer thin films and subsequent deposition of SiO2 particles. Plasma treatment rendered the film surfaces hydrophilic and led to the formation of fibrillar patterns. The plasma-treated film surfaces were compatible with multilayers acquired via LbL assembly, and the outer adsorbed polyelectrolyte layer determined the charge of the multilayer surfaces. Negatively charged SiO2 particles were adsorbed to the positively charged surface of the multilayers. This process is potentially applicable to surface modifications of polymer materials by charged compounds.

In this manuscript, we present the hybrid materials with sulfur as an inorganic element. Initially, the network polymers with the polysulfide-bridged polyhedral oligomeric silsesquioxane were synthesized and mixed with polystyrene and poly(methyl methacrylate). The resulting polymer blends showed higher thermal degradation temperatures than that of the polymer matrix similarly as typical hybrids. Next, it was found that the sulfur-bridging networks can increase refractive indices of the polymer matrices. Moreover, it was revealed that the loss of Abbe numbers was hardly observed by blending to conventional polymers.

The effect of the Molecular weight dispersity (MWD) on the interfacial width between a hPS brush and unbound dPS matrix has been investigated by NR measurement. The intermixing between hPS brush with narrow MWD and dPS matrix hardly occurred even after thermal annealing at 398 K because of dry-brush regime. In contrast, the intermixing of hPS brush with broad MWD and free dPS proceeded to increase the interfacial width like a wet-brush condition, in spite of high grafting density.

The performance of a fast pixel array detector with a grid mask resolution enhancer has been demonstrated for X-ray photon correlation spectroscopy experiments., The performance of a fast pixel array detector with a grid mask resolution enhancer has been demonstrated for X-ray photon correlation spectroscopy (XPCS) measurements to investigate fast dynamics on a microscopic scale. A detecting system, in which each pixel of a single-photon-counting pixel array detector, PILATUS, is covered by grid mask apertures, was constructed for XPCS measurements of silica nanoparticles in polymer melts. The experimental results are confirmed to be consistent by comparison with other independent experiments. By applying this method, XPCS measurements can be carried out by customizing the hole size of the grid mask to suit the experimental conditions, such as beam size, detector size and sample-to-detector distance.

Novel horizontal-type time-of-flight neutron reflectometer SOFIA (SOFt Interface Analyzer) was installed in BL 16 of Materials and Life Science Experimental Facility at the Japan Proton Accelerator Research Complex (J-PARC). The design and performance of SOFIA reflectometer was described based on the preliminary results of the neutron reflectivity (NR) measurements of deuterated polystyrene (d-PS) thin films, Langmuir–Blodgett film and at deuterium oxide/ polymer brush interfaces. Time-resolved in-situ NR measurement at 1-min intervals was also demonstrated to observe interfacial mixing of d-PS on the PS brush surface during annealing.

The authors described a region-selective immobilization methods of bacteria by using superhydrophobic/superhydrophilic and superhydrophobic/poly(ethylene glycol) (PEG) micropatterns for culture scaffold templates. In the case of superhydrophobic/superhydrophilic micropatterns, the superhydrophobic surface was prepared first by microwave-plasma enhanced chemical vapor deposition (MPECVD) from trimethylmethoxysilane. Then the superhydrophilic regions were fabricated by irradiating the superhydrophobic surface with vuv light through a stencil mask. In the case of the superhydrophobic/PEG micropatterned surfaces, PEG surfaces were fabricated first by chemical reaction of ester groups of p-nitrophenyl PEG with NH2 group of NH2-terminated self assembled monolayer from n-6-hexyl-3-aminopropyltrimethoxysilane. The superhydrophobic regions were fabricated by MPECVD thorough a stencil mask. In this study four bacteria were selected from viewpoint of peptidoglycan cell wall (E. coli versus B. subtilis), extracellular polysaccharide (E.coli versus P. stutzeri, P. aeruginosa), and growth rate (P. stutzeri versus P. aeruginosa). The former micropattern brought discrete adhesions of E. coli and B. subtilis specifically on the hydrophobic regions, Furthermore, using the superhydrophobic/PEG micropattern, adhesion of bacteria expanded for E. coli, B. subtilis, P. stutzeri, and P. aeruginosa. They observed a high bacterial adhesion onto superhydrophobic surfaces and the inhibitive effect of bacterial adhesion on PEG surfaces.

In order to improve the energy-conversion efficiency in fuel cells, the authors loaded Pt nanoparticles on carbon nanoballs (CNBs) by using solution plasma processing (SPP) involving CNB and Pt ion with a protection group. In this study, we employed poly(vinylpyrrolidone) (PVP) or sodium dodecyl sulfate (SDS) to prepare Pt nanoparticles supported on CNB (Pt/CNB) by the SPP, and the electrochemical properties as a catalyst was evaluated by cyclic voltammetry. The carbon nanoballs were prepared by thermal decomposition process of ethylene and hydrogen gases. Color of the solution changed from yellow to dark brown as synthesis time. This change indicates the improvement of dispersibility of CNB. Moreover, transmission electron microscopy images and elemental mapping images showed the Pt nanoparticles supported on CNB. A catalytic activity of the Pt/CNB in use of SDS was shown to be higher than the Pt/CNB prepared with PVP system. The SDS-containing Pt/CNB also showed the higher activity than that obtained by the conventional method.

Gold nanorods protected by hexadecyltrimethylammonium bromide were treated by an organosilane, aminopropyltriethoxysilane (APS) or vinyltrimethoxysilane (VS) in the presence of mercaptopropyltrimet...

The topics focusing on functionalization of gold nanorods have been reviewed with a view toward their advanced uses. In most cases, as-prepared gold nanorods are hydrophilic and protected by surfactants, since anisotropic growth of gold nanorods by chemical, electrochemical, and photo-induced methods is carried out in aqueous media in the presence of surfactants and additives. Since solvophilicity of gold nanorods predominantly affects on their optical properties, the control of dispersity of gold nanorods in matrices has been performed, without loss of their optical characters, by surface modification and hybridization with small molecules or polymers. As a result of the functionalization procedure, the capability of self-assembly of gold nanorods has been improved. Furthermore, the examples of application using gold nanorods demonstrate that gold nanorod is a promising material.

The gelation of sodium alginate incorporating gold nanorods was investigated. The hybrid gel was obtained by mixing calcium ions with a gel precursor (alginate + nanorod). The gel displayed two plasmon bands in the visible and near-infrared region. The shapes of the hybrid gel grains were controllable, like sphere, ring, and rod. Furthermore, the release of the gold nanorods from the gel phase was observed in a saline solution, accompanying the gel collapse to alginate fibers. Moreover, in the structural investigation of the hybrid gel using small-angle X-ray scattering, it was confirmed that alginate fibers were tightly condensed on the nanorod and formed a shell on it. Such condensation or shell formation resulted from the electrostatic interaction of alginate with hexadecyltrimethylammonium bromide, which protects the nanorods. The hybrid gel retained the same amount of water as the neat gel, although the water content (30 wt %) in a shell on a nanorod was far less than that (98 wt %) of bulk gel.

Hydrophobic gold nanorods were fabricated from hydrophilic gold nanorods coated with hexadecyltrimethylammonium bromide by treating with mercaptopropyltrimethoxysilane (MPS) and subsequently octadecyltrimethoxysilane (ODS). The fabrication of the hydrophobic shell went through the process of (1) binding MPS onto the nanorods, (2) hydrolysis of methoxysilanes, and (3) immobilization of ODS by dehydration condensation. The 2- or 3-D ordered structures of hydrophobic nanorods were self-assembled by the evaporation of solvent on a substrate. The aspects of 2-D assemblies were dependent on the concentration of the nanorods, as was seen in transmission electron microscopic images. At a low concentration, the nanorods assembled parallel to the substrate, whereas they stood on the substrate at a high concentration. On the other hand, in a solid of the gold nanorods, the formation of the 3-D assembly was confirmed by small-angle X-ray scattering. The assembly consisted of hexagonal arrays of the gold nanorods and their lamellar accumulation.

We synthesized hydrophilic and hydrophobic carbon nanoparticles (CNPs) by femtosecond laser (0.8 µm, 40 fs) irradiation of the water layer of an aerated benzene/water (B/W) bilayer solution. Focusi...

We fabricated an array of molecular devices with a simple vertical metal-molecule-metal (MMM) junction. The nano via holes are formed in SiNx or SiO 2 layer by RIE to contain the molecules inside. Finally, the top Ti/Au contact has been deposited by e-beam evaporation with cooling stage. By using self-assembly process, the organic molecules dissolved in dry and oxygen-free THF are inserted to the nanopore array device for 24 hours. We used the newly synthesized compound 4-[4-(3,5-Dimethyl-phenylethynyl)-3-nitro-phenylethynyl]-benzenethiol (DN), which is designed for adding two methyl groups at 3,5 position of phenylethynyl group of Tour's compound (4-(2-Nitro-4-phenylethynyl-phenylethyyl)-benzenethiol). The molecular devices produced the diode-like I-V characteristics and were implemented to logic gate with 3 × 3 array devices containing the DN molecule.

Hybrid Langmuir and Langmuir-Blodgett monolayers of a perfluorooctadecanoic acid mixed with a rigid block copolymer, poly(3,5-bis(3,5-bis(benzyloxy)benzyloxy)benzyl methacrylate-random-methacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), which is composed of benzyloxy dendron side chains and perfluorinated side chains, were prepared and characterized by surface pressure–surface area isotherms, atomic force microscopic images and neutron and X-ray reflectometries. The two-dimensionally phase-separated structures of monolayer films and their morphologies with plateau and terrace were confirmed. The monolayers were separated into a dendron layer, a perfluorinated layer, and a carboxyl layer. The layer formation is originated not only in the intermolecular interaction between a perfluorooctadecanoic acid and a block copolymer but also in the geometry of the molecules. Especially, the amphiphilicity of perfluorinated surfactant plays a role to the ordered array of the block copolymers.

The multilayers of poly(amido amine) dendrimer (fourth generation amine-terminated, G4NH2) and conducting sulfonated polyaniline (SPANI) were successfully deposited onto solid substrates by alternatively dipping in SPANI and G4NH2 solutions. Multilayer growth was monitored by ultraviolet−visible absorption spectroscopy and Fourier transform infrared-reflection absorption spectroscopy, which revealed an adsorption−desorption phenomenon, although it was sensitive to the concentration and pH of solutions. The average thickness of the SPANI/G4NH2 bilayer obtained from X-ray reflectivity is much smaller than the diameter of G4NH2 with an ideal spherical structure, suggesting that the dendrimer molecules in multilayers are highly compressed along the surface normal. Electron density profiles indicate that the multilayers are highly interpenetrated, and the thickness and molecular arrangement in the multilayers depend on the pH of G4NH2 solutions. Cyclic voltammograms of the multilayers in acidic and neutral ele...

New silsesquioxane incorporating a carbazole groups (PCTSQ) has been synthesized by a click thiol-ene reaction and a subsequent sol-gel reaction. To evaluate the electric property of this hybrid, diode devices have been fabricated by using PCTSQ thin film by spin-coating onto n-type ZnO film prepared by the electrodeposition method. The thin film hybrid devices showed good electric characteristics and high rectification ratio, as well as worked as a rectifier.

Neutron reflectometry is a powerful method for investigating the surface and interfacial structures of materials in the spatial range from nanometers to sub-micrometers. At the Japan Proton Accelerator Research Complex (J-PARC), a high-intensity pulsed neutron beam is produced with a proton accelerator at 220kW, which will be upgraded to 1MW in future. Beamline 16 (BL16) at the Materials and Life Science Experimental Facility (MLF) in J-PARC is dedicated to a horizontal-type reflectometer, and in this beamline, neutrons are transported downward at two different angles, 2.2° and 5.7° , relative to the horizontal. In December 2008, we started to accept the neutron beam at BL16 with the old ARISA reflectometer relocated from the KENS facility, KEK, Japan; and we have now replaced it with the brand-new reflectometer SOFIA (SOFt Interface Analyzer). With a high-flux beam and instrumental upgrade, the observable reflectivity of SOFIA reaches around 10−7 within a few hours for specimens on 3” substrates. In this paper, we will present the design and performance of the SOFIA reflectometer, and discuss some preliminary results on the device development for further upgrade.

Hydrophilic polymers show unique characteristics at various interfaces. High-density hydrophilic polymer brushes nano-coatings were prepared on Si-wafer and various substrates by surface-initiated controlled radical polymerization. Chain conformation at liquid/solid liquid/solid interface was characterized by neutron reflectivity. Applications of polymer brushes as structural nano-coatings such as super hydrophilicity, antifouling behavior, low friction behavior, and intelligent adhesion are presented.

Thin functional organic films on a gold substrate were fabricated by adsorbing tetrakis(carboxyphenyl)porphyrin (TCPP) on a spacer layer, which was prepared by the layer-by-layer adsorption of a dendrimer and a linear polymer. The thickness and photoluminescence of the films were investigated by surface plasmon resonance and surface plasmon fluorescence techniques, respectively. TCPP adsorbed on the spacer layer in aqueous solutions of different ionic strengths resulted in a thick TCPP adlayer at high ionic strength and a shrunk spacer layer at low ionic strength. The fluorescence was quenched at high ionic strength but could be observed at low ionic strength. The effects are explained by the states of dye aggregation. This study shows the control of energy transfer from a metal surface to a dye layer by changing the dye adlayer. It can contribute to the development of molecular devices involving energy-transfer systems.

Cationic and zwitterionic polyelectrolyte brushes on quartz substrate were synthesized by surface-initiated atom transfer radical polymerization of 2-(methacryloyloxy)-ethyltrimethylammonium chloride (MTAC) and 2-(methacryloyloxy)ethyl phosphorylcholine (MPC). The effects of ionic strength on brush structure are investigated by neutron reflectivity (NR) in NaCl deuterium oxide (D2O) solutions. We observed that poly(MTAC) chains were drastically shrunk at concentrations above 0.1 M NaCl/D2O, which may be the change in charge-screening effect against ions on poly(MTAC). On the other hand, effect of salt concentration on a swollen state of poly(MPC) brush was negligible, even at the high concentration (5.0 M) close to saturation. The behaviour of poly(MPC) in salt aqueous solution is completely different from that of poly(MTAC), which may arise from the unique interaction properties, neutral nature, and hydrated water structure of phosphorylcholine units.

X-ray photon correlation spectroscopy system was setup at SPring-8, BL19LXU, and the partial coherence scattering data from the silica particles grafted with polymer brush in polystyrene matrix were measured. Firstly, the static speckle patterns were checked. Below the glass transition temperature of polystyrene (Tg), speckles were clearly observed, on the other hand, above Tg, the scattering patterns became smooth and speckles were hardly observed. These variances of the speckle patterns result from the particle motion. Secondly, from the time variance of the speckle data, time autocorrelation functions g2(q,t) are calculated. While the flat behaviour of g2(q,t) without relaxation were observed below Tg, the relaxation behavior with relaxation time~100–101 were observed above Tg

The chain dimensions of free and immobilized polysulfobetaine in aqueous solution at various salt concentrations were investigated by size-exclusion chromatography with multiangle light scattering and neutron reflectivity measurement, respectively. The dependence of the z-average mean square radius of gyration ( z1/2) on the weight-average molecular weight (Mw) of free poly(3-(N-2-methacryloyloxyethyl-N,N-dimethyl)ammonatopropanesulfo-nate) (MAPS) in aqueous solution at salt concentrations of 74, 100, 200, and 500 mM was described by the perturbed wormlike chain model using the chain stiffness parameter λ−1 the molar mass per unit contour length ML, and the excluded volume effect B. B increased from 0 to 1.8 nm with increasing salt concentration to 500 mM due to the screening of attractive electrostatic interaction between ammonium cations and sulfonyl anions by salt ions. The swollen structure of the poly(MAPS) brush in D2O changed from a shrunken state to a relatively extended state with increasing salt concentration from 0 to 500 mM NaCl/D2O solution. The thickness of the swollen poly(MAPS) brush in 500 mM NaCl/D2O was 9.0 times greater than 2 z1/2 of free poly(MAPS) due to high osmotic pressure generated by the excluded volume effect of densely grafted polymer chains.

A novel neutron reflectometer with horizontal geometry will be established at BL16 in Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC) as a successor of a reflectometer ARISA-II. ARISA-II corresponding to a single neutron beam downward at 2.22 deg has achieved off-specular and time-resolved reflectivity measurements. The novel reflectometer is designed so as to receive two tilted neutron beams (2.22 & 5.71 deg), which gives us an opportunity in investigation on a free liquid surface. The reflectometer can provide a micro-sized beam by slit collimation and obtain a fair reflectivity with small sample area. Also, T0 chopper and neutron focusing mirror are newly introduced. The T0 chopper can suppress the background due to fast neutrons. The focusing mirror produces further reduction of measurement time not only for specular reflection by focusing neutrons on a sample, but also grazing incidence small-angle neutron scattering (GISANS) measurements by focusing on a detector.