We observed neurons cultivated on an indium tin oxide (ITO) substrate using scanning electron microscopy (SEM) whose high spatial resolution allows us to observe neuronal morphological details. First, we optimized the fixation condition of cultivated neurons for SEM observation. The first fixation with paraformaldehyde and glutaraldehyde,and the second fixation with OsO₄ were both necessary to avoid cell removal during the preparation before SEM observation. After optimization, we examined the morphological changes of neurons under an apoptotic condition,induced by staurosporine, by using both SEM and an immunochemical technique. Interestingly, the addition of staurosporine induced both apoptosis and a necrotic phenomenon. Immunostaining analysis revealed late-stage apoptosis after early-stage apoptosis, which was observed induced in cortical neurons by staurosporine for the first time. We confirmed that the SEM imaging of neurons is very useful as regards observing the apoptotic process. It is also a promising tool for understanding such neuronal activities as synaptic formation and axonal growth. Further examination of the interaction between neurons and substrates will contribute to the implementation of the artificial neurological devices. [DOI: 10.1380/ejssnt.2014.179]

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A wet chemical process was used for low-cost fabrication of Ag₂S flat thin films on the Ag electrodes utilized for an atomic switch. By precisely controlling the dipping condition, a flat thin film of β-Ag₂S (cubic) was successfully fabricated. When a Ag thin film was dipped into a 0.01%-Na₂S aqueous solution, α-Ag₂S (monoclinic) was first precipitated, and then β-Ag₂S, a Ag(I) ion conductor, was precipitated on the surface after dipping for 12 h. Because the ion-conduction in β-Ag₂S is much larger than that in α-Ag₂S with negligibly small, the results are important information for utilization of Ag₂S for electric devices such as atomic switch. By combining the fabricated β-Ag₂S electrodes with an organic field effect transistor structure, a Ag wire was grown on the surface of the β-Ag₂S electrode only when the FET was in the “on” state. [DOI: 10.1380/ejssnt.2014.185]

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I describe my personal view of impacts, prospects and vision of STM. I also mention the link between Marseille and Rohrer sensei, and his STM heritage. [DOI: 10.1380/ejssnt.2014.189]

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In an earlier paper [S. Yoshimura et al., Appl. Surf. Sci. 257, 192 (2010)], it has been demonstrated that indium (In) implanted silicon dioxide (SiO₂) thin films catalyze a reaction of benzhydrol with acetylacetone. In this study, it is found that the threshold In ion incident energy for manifestation of the catalytic effect exists between 400 and 470 eV. Furthermore, a technique to implant gallium (Ga) to SiO₂ films has been developed with highly controlled doses and injection energies for the formation of thin films that promote Ga catalysts. The efficiency of catalytic reactions by Ga implanted SiO₂ thin films is yet to be improved. Unlike In implanted SiO₂, the reason why no significant reaction was observed in the case of Ga implanted SiO₂ films examined in this study seems that the Ga ion energy was so low that deposited surface Ga atoms should lack interactions with Si atoms for the manifestation of catalytic reaction. [DOI: 10.1380/ejssnt.2014.197]

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In order to gain better understanding of the 2D subband formation in the space charge layer of Si(111)-β√3 × √3-Bi, we have performed scanning tunneling microscopy and spectroscopy studies on the surface at 77 K. This surface is identified as an insulator the band gap of which is larger than that of Si. The dI / dV measurements inside the surface band gap reveal that band bending reaches −0.15 eV at the interface, which corresponds to the quantumwell depth of this system. In addition to the bulk and interface CBMs, an additional state can be found between them. This state is attributed to the bottom of the 2D subband state, since the energy position is in a good agreement with that obtained by semi-classical calculation. [DOI: 10.1380/ejssnt.2014.217]

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In order to understand the effects of the polymorphism to the electronic structures of the Fe-phthalocyanine (FePc) crystals, we have performed first-principles calculations by using full-potential linearized augmented planewave method based on constraint density functional theory. From the total energy calculations for the electronic configurations of the ³A_2g and ³E_g states, by varying the crystal parameters of a tilt angle of the molecular plane with respect to the molecular stacking direction and a distance between the neighboring inter-molecular planes, we find that the structural polymorphism plays an important role in determining the ground state electronic configurations. [DOI: 10.1380/ejssnt.2014.221]

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Nano-carbons such as carbon nanotubes and graphenes are very promising as next-generation materials, and field effect transistors (FETs) can be used with nano-carbon channels. In these nano-carbon materials, carbon nanowalls (CNWs) are constructed with a few layers of graphene and exhibit properties similar to those of graphene. We have developed a self-aligned process for CNWs using grapho-epitaxy. We have grown CNW channels on several line and space patterns fabricated by electron beam lithography and reactive ion etching. When the line and space pattern is suitable, self-aligned CNWs can be made by plasma-enhanced CVD. We also discuss the electrical properties (I_DS-V_DS characteristics) of the self-aligned CNW-FETs resulting from several growth temperatures and deposition times. [DOI: 10.1380/ejssnt.2014.225]

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TiN(001)/MgO(001) interfaces have been investigated by using the total energy pseudopotential method. Their relaxed interface structures and electronic properties (charge densities, electronic band structures, density of states,etc.) were obtained. All the calculated electronic states of the TiN/MgO interfaces correspond to metallicity. Upon full structural relaxation of these interfaces, the cation (Ti) and anion (N) atoms on the interface layer are rumpled. This trend of atomic displacements at the interface layer is similar to that observed in the rumpled surface layer of transition metal carbides (TMCs) and nitrides (TMNs). We calculated the energies of two bonding configurations at the TiN/MgO interface. One is a cation-anion (Ti–O and Mg–N) bonding configuration across the interface. The other is a cation-cation (Ti–Mg) and anion-anion (N–O) bonding configuration across the interface. The former is energetically more stable than the latter by 2.31 eV. We investigated the TiN/MgO interface with a oxygen vacancy (O vacancy) for both of the abovementioned two bonding configurations. The formation energies of the O vacancy for the TiN/MgO(IV) and TiN/MgO(X) bonding cases are 6.90 eV and 6.79 eV, respectively. These values are positive and large. This indicates that the TiN/MgO interface with the O vacancy is energetically unfavorable. [DOI: 10.1380/ejssnt.2014.230]

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We propose a new electromagnetic shielding (EMS) sheet that uses carbon nanotube (CNT)-composite paper. The electromagnetic environment in which electronic devices such as mobile phones and personal computers operate has become increasingly complex due to increased electromagnetic noise. This noise can cause unexpected behavior in electronic devices. Therefore, EMS sheets are required to shield devices from this noise. Carbon-nanotube composite paper has high electrical conductivity despite being a paper and does not deteriorate like metallic materials which are commonly used for EMS sheets. In this study, we aim to use CNT-composite paper to develop new EMS sheets that have a high shielding effectiveness (SE) (over 30 dB) at frequencies in the 0.1 MHz to 1 GHz range. To achieve this, we made test samples and measured their SE with the Kansai Electronic Industry Development Center (KEC) method. The first CNT-composite paper we developed achieved an SE of 20-50 dB from 0.1 MHz to 100 MHz. However, the SE was 16 dB in the GHz band. To increase the SE in this band, we designed and simulated many different shapes of shielding sheet which we then fabricated to measure their SE. We obtained positive results, indicating that a new shielding paper shape has a higher SE in the GHz band. [DOI: 10.1380/ejssnt.2014.242]

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Gold decorated titanate nanowires and nanotubes were investigated by XPS, XRD and HRTEM. XPS and UV-Vis diffuse reflectance results suggested that a certain part of gold underwent an ion exchange process. Higher gold loadings lead to the formation of nanosized-dispersed particles complexed to oxygen vacancies, with a diameter distribution of 1.5-10 nm. Gold additives catalyzed the transformation of the tube structure to anatase. Gold, however, stabilized the wire-like structure up to 873 K. [DOI: 10.1380/ejssnt.2014.252]

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Basic photoluminescence (PL), scintillation and thermoluminescence (TL) properties of Cu-doped ZnO thin films deposited by the Liquid Phase Epitaxy (LPE) method are reported. When the films were excited with 280 nm LED,the emission band was detected at 510 nm wavelength. This emission originated from the recombination between neutral shallow donor levels related to oxygen vacancy and the t² energy level of excited Cu²⁺ (d⁹) accepter. The PL quantum efficiency was estimated to be about 3%. The pulse height spectra recorded under ²⁴¹ Am alpha-ray irradiation indicated that the Cu-doped film had scintillation light yield greater than that of Bi₄Ge₃O₁₂ (BGO) commercial scintillator. [DOI: 10.1380/ejssnt.2014.275]

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In this paper, we have reported the structural, morphological and optical studies of pure and Mn-doped ZnO nanoparticles synthesized by the simple solution combustion method. The structural, morphological and optical studies are carried out by powder XRD, FE-SEM, HR-TEM, Raman, UV-vis absorption and PL spectra. The XRD pattern indicates that the prepared particles are in hexagonal wurtzite structure with the crystalline size of around 30-60 nm. The FE-SEM and HR-TM images are coincide with each other for aggregation of particles nature. The elemental analyses of pure and doped samples are evaluated by EDX. Raman spectra of the samples show remarkable result in the polar and non-polar branches. Room temperature PL shows the near band edge related emission and the results are related several intrinsic defects in the Mn-doped ZnO nanoparticles. Blue shift of the UV emission has occurred in all the doped samples attributable to Burstein-Moss shift. [DOI: 10.1380/ejssnt.2014.283]

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We grew GaSb QDs on GaAs (111)A by molecular beam epitaxy (MBE). By atomic force microscopic studies, it was found that large GaSb islands with low density are formed when grown at a relatively high temperature (T_s ∼ 470°C), suggesting the large diffusion length of Ga atoms on the substrate surface. In contrast, GaSb QDs formed at a lower temperature (T_s ∼ 430°C) are much smaller (∼ 39 nm) in diameter and their density is much higher (∼ 5.0×10¹⁰ cm⁻²), originated from the suppression of the Ga diffusion on the substrate surface. We also grew GaSb QDs at various substrate temperatures T_s and examined how T_s affects the QD radius and height. [DOI: 10.1380/ejssnt.2014.304]

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Potassium (K) adsorption on coronene, picene and [6]phenacene monolayers, which serves as a model system for the metal-intercalated aromatic superconductors, was studied in a molecular scale. Scanning tunneling microscopy (STM) on the K-doped monolayers revealed drastic rearrangements of the molecular layers. Besides the overall similarity of the molecular arrangement in the doped phase, fine structures and unit cell sizes were different, depending on the host molecules. The overall similarity in the structures of the K-doped monolayers should be in close relation to the superconductivity on these systems. [DOI: 10.1380/ejssnt.2014.330]

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Zinc Oxide (ZnO) thin films have been grown by radio frequency plasma enhanced chemical vapor deposition (PECVD) technique on silicon wafers and corning7059glass substrates kept at different substrate temperatures. Diethylzinc (DEZ) was used as the source precursor for the preparation of ZnO films, H₂O and argon were used as oxidizer and carrier gases respectively. Structural and optical properties of the films, grown with different gas flow ratio, were investigated using various characterization techniques. The as grown ZnO films at a substrate temperature of 300°C with DEZ/H₂O flow rate ratio 1:4 at 50 W of R. F. power were found to be highly c-axis oriented with (002) preferred orientation. The elemental analysis of these films performed using X-ray photoelectron and Auger electron spectroscopy showed the presence of zinc and oxygen only. Atomic force microscope images of the films exhibited columnar grain growth. The films showed a transmittance (> 85%) in the 400-800 nm wavelength range. The optical band gap for film deposited at 300°C estimated using Tauc’s plot was found to be ∼3.28 eV. [DOI: 10.1380/ejssnt.2014.334]

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Computational model for AFM using the coupling method of molecular dynamics (MD)and continuum is proposed in order to investigate mechanism of the observed energy dissipation in AFM. The motion of cantilever is described by a spring, and the atomic interaction between the tip attached on cantilever and surface is calculated by MD method. The motions of the spring and atoms are coupled by the MD/continuum hybrid method. We find that a significantly energy dissipation comes from atomic thermal fluctuation between the tip and surface. To further study this dissipation mechanism, the temperature and frequency dependence of the dissipation is investigated. [DOI: 10.1380/ejssnt.2014.339]

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Iron oxides have attracted a great deal of attention among specialists because of their multivalent oxidation states. The β-iron oxide nanoparticles have been synthesized by adding a Eucalyptus globulus leaf extract into the aqueous solution of ferric chloride. The synthesized nanoparticles were characterized by Ultra Violet - Visible spectrum (UV-Vis), X-Ray diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Fourier Transform Infra Red spectroscopy (FT-IR). TEM and SEM image shows the nanostructures of prepared iron oxide nanoparticles. The XRD and UV-Vis spectrum confirmed the prepared iron oxide nanoparticles β in phase. [DOI: 10.1380/ejssnt.2014.363]

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C-axis epitaxial Cr₂O₃ thin films were prepared on Pt by radio-frequency (RF) magnetron sputtering method with an in-situ reflection high energy electron diffraction (RHEED) system. Leakage current of Cr₂O₃ which is deposited at 480°C is the lowest and the value shows 10⁻⁶-10⁻⁷ A/cm² order and magnetic hysteresis was observed. This magnetization is induced at Cr₂O₃/Pt interface and this could be due to compressive stress from Pt substrate, and magnetoelectric (ME) effect could be modulated by interaction between interface and Cr₂O₃. [DOI: 10.1380/ejssnt.2014.373]

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The configuration of asymmetric dimers on the Si(001)2×1 surface was investigated at room temperature (RT) and high temperature (HT) by measurements of many-beam rocking curves of reflection high-energy electron diffraction (RHEED). We propose a novel projected potential approach for analyzing the dynamic structure of the Si(001)2×1 surface, on which high frequency flip-flop of asymmetric dimers occurs. This method is based on reciprocal lattice rods in the 0th Laue zone, which represent Fourier components of the projected crystal potential along the incident azimuth, so that the cross-sectional surface structure that is perpendicular to the incident azimuth can be investigated. It has been confirmed that this approach is effective for such dynamic surface structures with randomly flipping dimers. The asymmetric dimer configuration for the Si(001)2×1 surface at RT was determined to be fundamentally the same as that for the static Si(001)c(4×2) surface. The dimer relaxation into a symmetric configuration was confirmed to occur at a HT of approximately 1000 K. [DOI: 10.1380/ejssnt.2014.380]

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It is shown that neutral particles moving above modulated surfaces undergo selective attractive or repulsive forces which in a resonance way depend on transition frequencies between internal energetic levels and the velocity of atom motion. The interaction of hydrogen atoms with surface-inhomogeneous periodic electric fields of crystallographic planes of ionic and ionic-covalent crystals is studied. It is investigated the possibility of application of such interactions for the obtaining of monochromatic by velocities one-component atom beams and also for the classication and separation of multi-component beams of particles for the determination the degree of ionicity,etc. [DOI: 10.1380/ejssnt.2014.387]

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Ni nanoparticles formed on SrTiO₃ (001) and (110) surfaces are investigated from both horizontal and vertical directions by STM and TEM. Structures and morphologies of the nanoparticles were investigated, and their dependences of morphologies and interfacial structures on surface orientations were found out. Ni nanoparticles mostly possess the modified Wulff construction. While nanoparticles on SrTiO₃ (001) mostly have Ni {001} interfaces, those on SrTiO₃ (110) have either Ni {110} or Ni {111} interfaces. [DOI: 10.1380/ejssnt.2014.391]

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Optical and scintillation properties of GaN crystalline film were investigated. It showed 30-50% in-line transmittance at wavelength longer than 400 nm and intense emission appeared at 365 nm under 213 nm excitation in photoluminescence (PL) spectrum. When PL decay time was investigated under 280 and 200 nm excitation, luminescence decay time resulted few ns. In X-ray induced radioluminescence spectra, intense emission appeared at 365, 420, and 550 nm. The former one was ascribed to the exciton emission and the latter two would be due to defects related emission. Scintillation decay time of GaN was quite fast as few ns which was consistent with PL results and no slow component was observed. [DOI: 10.1380/ejssnt.2014.396]

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For TOF-SIMS characterization of lithium reaction products on electrodes of lithium air batteries (LAB), characteristic secondary ion species were found for identification and differentiation of their chemical states utilizing gas cluster ion beam (GCIB) sputtering for surface stabilization. Lithium peroxide and related products such as carbonate and formate were identified and confirmed under coexistence of electrolyte components to be produced on the real LAB carbon cathode by conducting discharge experiments using ¹⁸O₂ reaction gas, which would be suitable method for further investigation on mechanisms of related electrode reactions. [DOI: 10.1380/ejssnt.2014.75]

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Nano alloys based on platinum form the basis for automobile exhaust catalyst, one of the most successful and important families of heterogeneous catalysts used in industry today. In this study, the structure of Pt–Pd catalyst is analyzed by atom probe tomography (APT). APT which has high spatial resolution and high detection sensitivity with single atomic level is widely used in the world in order to evaluate atomic structure of metals and semiconductor materials as typified by field effect transistor. The transformation of catalyst surface composition was observed by several thermal and environmental conditions in order to discuss the deterioration of catalyst. To observe the existence of catalytic reaction under APT condition, the field evaporated ions which originated from C_xH_y thin film on Pt–Pd or W needle were compared. In the result of this study, the transformation of composition at surface micro region occurs by thermal treatment of Pt–Pd alloy. [DOI: 10.1380/ejssnt.2014.145]

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The most striking characteristic of observations that use synchrotron radiation is that a material’s structural changes can be observed in situ during a specific reaction under conditions closely resembling the actual process or environment of interest, and on a time-scale that can resolve fine details of the process (dynamic observation). To make the most of these advantages, we have developed various unique analytical techniques using special reaction cells for in situ and dynamic observation using synchrotron radiation in order to clarify reaction mechanisms of various materials and processes. After reviewing various techniques using synchrotron radiation, recent approaches of quick-XRD (QXRD) and dispersive-XAFS (DXAFS) and their application to sintering reactions in the ironmaking process and reduction-oxidation (redox) reactions in oxide catalysts are discussed in details. The change in atomic structure as well as microstructure could be in situ and dynamically observed with a time-resolution of a few sec. up to 1773 K, revealing the mechanism of formation of Ca–Fe–O oxides form the oxide molten. The change in structure of nano-clusters was successfully observed with a time-resolution of a few m-sec. During redox-gas cycles up to 1223 K, revealing the mechanism of Pd/Sr–Fe–O catalysis for automotive emission control. [DOI: 10.1380/ejssnt.2014.165]

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Recent progress on aberration correction optics and single atom spectroscopy techniques increase needs of higher brightness electron sources than conventional single crystalline tungsten emitters. For this purpose, we are trying to fabricate a self-aligned nano-structured electron emitter using a field emission induced growth (FEIG) method in a field emission microscope (FEM) apparatus. The growth process can be monitored by the FEM, so that it is possible to control the nano-emitter size. A fabricated nano-emitter was mounted on a commercially available field-emission scanning electron microscope (FE-SEM) and its practicality was investigated. As compared with a carbon nanotube (CNT) emitter, the nano-emitter achieves larger beam current (better image contrast) and shows higher vibration durability. Emission stability of the nano-emitter is also within practical level, so that it was demonstrated that the FEIG nano-emitter could be a leading candidate for substituting conventional field emitters. [DOI: 10.1380/ejssnt.2014.192]

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We entered the 21st Century witnessing several remarkable progress in Science and Technology. Novel materials and devices once considered stuffs of science fiction are, one after another, becoming reality. It would not be an exaggeration to say that we are coming to the Age of Designer Materials —Functional materials that have many varied and competing ground states, allowing us to switch the specific properties using external stimuli, e.g., heat, pressure, electric field, and magnetic field. Here, we present some non-traditional theoretical views developed in our group. The unifying themes are: quantum effects, complexity and functionality. We emphasize the unique role played by the Surface/Interface for providing a special environment (a foundation) for realizing Designer Materials, that are not realizable in the bulk and the strategic choice of particular elements as building blocks, e.g., for Exhaust Purification, Memory Devices and (Nano) Spintronics Applications. [DOI: 10.1380/ejssnt.2014.203]

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The influence of electron beam focusing to SEM image sharpness has been studied by a Monte Carlo simulation method and an electron probe focusing model. The Monte Carlo simulation of the SEM image is based on a well-developed physical model of electron-solid interaction, which employs Mott’s cross section and a dielectric functional approach for electron elastic and inelastic scattering, respectively. A series of simulated SEM images for a practical sample, gold particles on a carbon substrate, are generated for different electron beam focusing conditions. For sharpness measurement three methods recommended by ISO/TS 245697 are used. The variation of image sharpness with the electron beam focusing condition is studied in detail. [DOI: 10.1380/ejssnt.2014.247]

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An optical sum frequency generation (SFG) microscopy image of a fish scale of Pagrus major was observed. Its SFG spectra were also measured and were compared with that of collagen of Achilles tendon of a cow (Bos taurus). From this comparison, the peak near 2950 cm^-1 in the fish scale spectrum was assigned to the fish collagen. The two collagen spectra showed different line shapes and widths owing to a difference in the background nonlinearity. In the SFG image of the fish scale cross section, stronger signal was observed from the sea side than from the body side. [DOI: 10.1380/ejssnt.2014.259]

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We have prepared silver-loaded gallium oxide (Ag/Ga₂O₃) photocatalysts by the solution plasma method (SPM) and impregnation method (imp), and investigate the effects of the chemical states and the size of the Ag nanoparticles on their photocatalytic activities. The photocatalytic reduction of CO₂ with water proceeds over all the Ag/Ga₂O₃ photocatalysts to produce CO, however the CO production rates decrease during photocatalytic reaction. Measurements of UV-VIS diffuse reflectance spectra, XANES spectra and TEM images reveal the followings:the Ag oxide nanoparticles in the as-prepared Ag/Ga₂O₃ (imp) samples exist and their size distribution is wide from 5 to 10 nm. They become a lot of metallic nanoparticles by UV light-irradiation, and become larger particles with the size of ca. 20 nm during the photocatalytic reaction. On the other hand, the Ag nanoparticles in the as-prepared Ag/Ga₂O₃ (SPM) samples are metallic with the size of less than 10 nm. The size does not change under UV light irradiation, while become larger particles during the photocatalytic reaction as similar to the case of the Ag/Ga₂O₃ (imp) samples. Such small metallic Ag nanoparticles with the size of 5-10 nm are suitable for CO production. However, they aggregate during the reaction for 5 h to degrade the photocatalytic activity. [DOI: 10.1380/ejssnt.2014.263]

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Manganese oxide nanoparticles (Mn-O NPs) were prepared through our novel method as reagents for laser desorption/ionization mass spectrometry (LDI-MS). Through the control of the reaction time in the chemical preparation method (0.5, 1, and 5 h), we succeeded in preparing three different types of manganese oxide particles. The particles were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and DC magnetization measurements. These characterization results indicated that the manganese ions oxidized in aqueous alkaline solution, and that the spinel structure was retained for the Mn₃O₄ phase, which then gradually changed into the MnO₂ phase. The mass spectra of substance P (N.W. = 1347.6) were measured by PALDI-TOF mass spectrometry with Mn-O NPs. The Mn-O NPs that reacted with 3-aminopropyltriethoxysilane(γ-APTES) for 1 h or 5 h had higher ionization abilities than those reacted for 0.5 h. These different abilities are attributed to the different crystal structures of the prepared manganese oxides. [DOI: 10.1380/ejssnt.2014.269]

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SEMs are usually equipped with a backscattered electron detector and a secondary electron detector. In addition to these, alternative detectors have recently been employed to obtain images with additional information content. These detectors are designed to detect electrons emitted within a certain predefined range of energy and takeoff angle. However, no attempt has ever been made to design a detector that allows direct detection of electrons in a user-defined energy and takeoff angle range. In this study, an electron detector was designed and experimentally manufactured to detect electrons emitted in a defined, variable range of energy and takeoff angle. With this “E-θ detector” a set of images was taken to obtain electrons in two distinct ranges of energy and two distinct ranges of takeoff angle. These images were compared with those obtained by ordinary secondary and backscattered electron detectors. As an application example, clear contrast originating from crystal orientation of a spherical tungsten single crystal was observed in an image composed of high takeoff angle secondary electrons. [DOI: 10.1380/ejssnt.2014.279]

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Ag loaded Ga₂O₃ (Ag/Ga₂O₃) has exhibited photocatalytic activity for CO₂ reduction with water to produce CO as well as for water splitting to H₂ and O₂. In-situ FT-IR measurements have shown CO₃ stretching vibration bands assignable to carbonate and bicarbonate species when CO₂ molecules chemisorbed on the catalyst surface. These species change to bidentate formate species under photoirradiation. It subsequently converts to CO by interacting with water molecules, not chemisorbed OH on the catalyst surface. This result suggests that formate species is an intermediate of the photocatalytic CO₂ reduction. On the other hand, Au loaded Ga₂O₃ (Au/Ga₂O₃) has produced H₂ predominantly with a very small amount of CO formation, since the less amount of CO₂ molecules chemisorb on Au/Ga₂O₃. FT-IR measurements of the Ag/Ga₂O₃ with high Ag loading have shown carbonate species due to the adsorption of atmospheric CO₂ on hydroxyl group. The carbonate species is too unstable under photoirradiation to convert into formate species, but is stabilized as CO₃^2- species by the reaction with water. XANES analysis has revealed that atomically dispersed Ag metal species may be effective for the adsorption of CO₂ and the subsequent conversion into formate species to promote the photocatalytic CO₂ reduction. [DOI: 10.1380/ejssnt.2014.299]

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Spinel-structured manganese oxide (MMn₂O₄: M = Fe, Ni, Co, Zn) nanoparticles encapsulated in amorphous SiO₂ were produced using our original wet chemical method. From the X-ray diffraction patterns, the diameters were estimated to range from 4 nm to 23 nm, depending on the annealing temperature. Bulk manganese oxide crystals are known to have the spinel structure, and a tetragonal structure with Jahn-Teller distortion is a stable and normal phase. This Jahn-Teller distortion is induced by Mn³⁺ ions at the octahedral B sites. However, we have successfully produced cubic structures consisting of FeMn₂O₄, CoMn₂O₄, and NiMn₂O₄ nanoparticles in which the local distortion is suppressed. In order to clarify the local structure, X-ray absorption fine structure (XAFS) and magnetization measurements were performed. The cubic and tetragonal structures were selectively obtained, and their magnetic properties were investigated. [DOI: 10.1380/ejssnt.2014.307]

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The dendritic nanostructure was fabricated on a surface of tungsten plate by helium plasma irradiation. The nanostructure consisting of W metal was partially oxidized to form WO₃ on exposure to air, and the resulting surface exhibited a broad photoabsorption in the range from 1 to 5 eV. We examined photoinduced reaction of methylene blue (MB) on the material. It was found that the partially and fully oxidized surface nanostructures were able to promote a decolorization of MB under photoirradiation even with the near-infrared light (< 1:55 eV), whose energy is lower than the band gap of WO₃. The reaction rate was varied with the fraction of W and WO₃ on the surface layers, that is, the partially oxidized sample promoted the reaction at a higher rate than the fully oxidized one. It is also found that the reaction rate decreased with time, which would be caused by the products accumulation on the surface and the surface oxidation. [DOI: 10.1380/ejssnt.2014.343]

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Artifact-metrics authentication is a method to authenticate artifacts that have measurable intrinsic characteristics like microscopic random patterns produced in the manufacturing process. In this study, we use a single-walled carbon nanotube (SWCNT) composite paper that is a composite material made from the mixture of the SWCNTs and the pulp (paper materials), as the material of a new artifact-metrics authentication. Advantages of using SWCNT-composite papers, for example, are easy to handle and to make, and impossible to replicate the patterns. As authentication methods, we focus on the use of Raman spectroscopic characteristics of the SWCNTs, and use features of the distinctive SWCNT patterns in each paper, for authentication “keys.” The estimated result of error rate = 10^-5 or less was obtained from an experiment that used combination data obtained from specific Raman peaks of the SWCNTs. Our SWCNT-composite papers also have the other usable properties that can be used for authentication keys, thus we are able to improve authentication accuracy more using those keys. [DOI: 10.1380/ejssnt.2014.368]

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The caption of Fig. 2 in Ref. [1] should read “UV-Visible spectrum of 100 ml of 0.01 M aq. FeCl₃ and 20 ml of Eucalyptus globulus leaf extract mixture.”

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