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LiF–NixMn1−xO composites are prepared by the mechanical milling of LiF and NixMn1−xO (x ≤ 1) solid solution for 72 h. The obtained composites are examined by XRD, charge–discharge measurements, CV, and XPS. X-ray diffraction peaks of LiF–NixMn1−xO are broadened by milling. The diffraction peaks of NixMn1−xO in x

β-carotene (BC) is one of the naturally occurring dyes belonging to the carotenoids group. Although it is more environmentally friendly and better suited for humans compared with synthetic dyes, it destabilizes with light and heat, easily losing its color under irradiation. Extended application of BC are therefore limited. The aim of this study is to improve the stability of BC by intercalation into the montmorillonite layers modified with a cationic surfactant, by a simple mixing and minimal solvent use. The physical mixing of small quantities of concentrated BC/hexane solutions with organo-modified montmorillonite successfully resulted in the composite material. The length and the number of alkyl chains of the surfactant used for the organic modification influenced the stability enhancement of the incorporated dye. The improved stability of the dye molecules incorporated in the interlayer space was found to be due to restricted contact with atmospheric oxygen.

LiF–NiO composites are synthesized by the mechanical milling of LiF and Li-doped NiO (d_NiO) for 72 h. Li-d_NiO is prepared by the calcination of a mixture of Li2CO3 and NiO. The X-ray diffraction peaks of NiO are shifted by the doping and milling processes, while those of LiF disappear after milling. Rietveld analysis shows that the composites obtained by milling form solid solutions and that the Li+ and Ni2+ ions in them are disordered. LiF and Li-d_NiO samples milled individually do not exhibit a noticeable discharge capacity, while the composites show large values. The composite formed using undoped NiO without ball-milling shows a discharge capacity of 144 mA h g−1 at 0.05 C between 2.0 and 5.0 V, while the composite of LiF and 20% Li-d_NiO exhibits a discharge capacity of 247 mA h g−1. The rate capabilities of the composites increase with the Li content, and the discharge capacity of the LiF–Li-d_NiO (20%) is 146 mA h g−1 at 1 C for voltages of 2.0–4.8 V.

4LiF-NiMn 2 O 4 composites are synthesized by the mechanical milling of LiF and NiMn 2 O 4 in a molar ratio of 4: 1 for 36–192 h. The synthesized composites are investigated by XRD, charge-discharge measurements, and XPS. A broad XRD peak of 4LiF-NiMn 2 O 4 was observed and those of LiF and NiMn 2 O 4 disappear after the milling of 144 h and more. The discharge capacity of the 4LiF-NiMn 2 O 4 composites changes with the milling time, with the composite prepared by milling for 144 h exhibiting a discharge capacity of 256 mA h g −1 at 0.1 C for voltages of 2.0–4.8 V. With a cut-off voltage of 4.8 V or more, decomposition of the electrolyte proceeds along with the charge process, so the charge-discharge current efficiency deteriorates and the discharge voltage decreases. In the charge-discharge measurement without the capacity limit, although the charge-discharge efficiency was low due to the decomposition of the electrolyte, the high discharge capacity of 310 mA h g −1 was obtained. The XPS data suggests that the Ni 2+ ion and Mn 3+ ion are oxidized to Ni 3+ and Mn 4+ ion in charge process up to 4.8 V and are reduced to Ni 2+ ion and Mn 3+ ion during the discharge process.

MgAl2X8 (X = Cl, Br) was synthesized from MgX2 and AlX3, and the physical properties were evaluated by XRD, AC conductivity, and NMR. MgAl2Br8 has the same crystal structure as MgAl2Cl8 and belongs to the space group C2/c. MgAl2Cl8-yBry was also synthesized in the same manner as MgAl2Br8. MgAl2Cl8-yBry was found to have the same crystal structure as MgAl2Cl8 and forms a solid solution in all the synthesized compositions. From the Rietveld analysis of the XRD pattern, it was found that the arrangement of Cl and Br in the crystal had no order and occupied the halogen sites almost randomly. The AC conductivity of the obtained compound was lowest for MgAl2Cl8 and highest for MgAl2Cl2Br6. The conductivity of MgAl2Cl2Br6 at 400 K is 1.3 × 10−6 S/cm, and the Nyquist plot suggests that MgAl2Cl8-yBry is a magnesium ionic conductor. In the temperature range from room temperature to 412 K, there was no significant change in the 27Al NMR spectra of a MgAl2Br8 single crystal, and the effects of Mg2+ ionic conduction and the reorientation motion of AlX4ˉ anion were not observed.

ZnO 1− x S x films were deposited on quartz substrates by pulsed laser deposition (PLD) of ZnO 1− x S x targets. The ZnO 1− x S x films with S-contents of 0.03–0.17 were grown from the ZnO 1− x S x targets sulfured at temperatures of 200 and 500 °C. The resistivity of the ZnO 1− x S x films is slightly increased with the S-content. An increase of the O 2 -partial pressure in an atmosphere reduces the S-content in the films and drastically enhances the resistivity of the films. However, the carrier type of the films is still n-type. In order to incorporate excess S atoms into films, evaporation of Sulfur was performed during the PLD process. As a temperature of the S-evaporation is raised, the resistivity of the films is significantly enhanced and hole-conductivity appears in the films grown by the S-evaporation at 80 and 90 °C. By X-ray photoelectron spectroscopic measurements, the presence of SO x species is confirmed for the p-type ZnO 1− x S x film. Both interstitial SO 3 or SO 4 clusters and complexes of Zn-vacancy with H are considered to be appropriate acceptors responsible for the hole-conductivity at room temperature.

LiF-NiO composites in a molar ratio of 1:1 are synthesized by the mechanical milling of equal amounts of LiF and NiO for 12–144 h. The synthesized composites are investigated by XRD, charge-discharge measurements, and XPS. The XRD peaks of NiO broaden with an increase in the milling time, while those of LiF disappear. Rietveld analysis shows that the LiF-NiO composites prepared by milling for more than 72 h form a solid solution and that the arrangement of Li + and Ni 2+ ions in them is disordered. The LiF and NiO samples milled individually do not exhibit a noticeable discharge capacity, while the composites show a large one. Further, the discharge capacity of the LiF-NiO composites increases with the milling time, with the composite prepared by milling for 144 h exhibiting a discharge capacity of 216 mA h g −1 and an average voltage of 3.53 V at 0.05 C for voltages of 2.0–5.0 V. The XPS data suggest that the Ni ions are probably oxidized and reduced repeatedly during the charge-discharge process and that the Ni 2+ ions are partially oxidized to Ni 3+ ions during charging to 5.0 V.

β-carotene is one of naturally occurring dyes, and has been used as a colorant because of its nontoxicity and biological functions. However, the color stability of the β-carotene is not sufficient. The aim of this study is to enhance the stability of the β-carotene by incorporation into the pore of mesoporous silica. Although the highly lipophilic β-carotene does not generally meet rather hydrophilic inner pore space of mesoporous silica, the modification of the inner pore by alkyl chains enables the incorporation of the β-carotene into the mesopore. The incorporated β-carotene is successfully stabilized against visible light irradiation. Also improved is the durability of the dye in the composite sample against elution to the solvent. The effect of the complexation on the stability enhancement depends on the affinity of the lipophilic β-carotene to the organo-modified inner pore space.

Anthocyanin is known as a safe coloring material although its poor stability often limits more extended use. In this study, we tried the enhancement of the photostability of the anthocyanin by the incorporation into the pore of HMS type mesoporous silica containing various metal ions. The anthocyanin was adsorbed on the HMS by pouring a highly concentrated anthocyanin solution to the dried HMS, urging the incorporation of the dye into the mesopore by a capillary condensation. Improved stability of the anthocyanin against visible irradiation was achieved by the adsorption onto the HMS containing Fe 3+ , although other metal ions in the HMS showed less effect on the stabilization. From the UV–vis spectroscopy, the Fe 3+ species effective for the stabilization of the anthocyanin was found to be the tetrahedral one highly dispersed in the silica framework. The decrease in the absorptivity of the anthocyanin on the Fe-HMS compared to other metal-containing HMS suggested that the Fe-HMS promoted the aggregate formation of the anthocyanin molecules. The highly dispersed Fe 3+ species had an ability to gather the anthocyanin molecule close to itself, resulting in tight incorporation of the dye inside the mesopore. The incorporation and aggregate formation of the anthocyanin was expected to contribute to the improvement of the stability against irradiation.

β-carotene and annatto extract are typical carotenoids used as safe colorants for foods. However, the instability against irradiation limits their wide use. The improvement of stability was investigated by the intercalation of dye into the interlayer space of the anion-exchangeable clay, hydrotalcite. A hydrophobic environment was constructed in the interlayer space of the hydrotalcite by its modification with anionic surfactants (dodecyl sulfate and dodecylbenzene sulfonate). The lipophilic β-carotene and annatto dye were successfully incorporated into the organo-modified hydrotalcite, and the incorporated dyes exhibited improved photostability under visible irradiation from a 100 W halogen lamp (190 klux) in the air. The effect of the stabilization on the anionic annatto dye was higher by the incorporation in the modified hydrotalcite than that in the modified cation exchangeable clay, suggesting that the polarity of the clay sheet had some influence on the stabilization of the incorporated dye. The stabilization effect of β-carotene was not so significant as that of the annatto dye, because sufficient intercalation of non-polar β-carotene might require stronger hydrophobic environment. The π–π interaction between the β-carotene and the benzene ring of dodecylbenzene sulfonate was found to contribute to the stability enhancement.

Because of its non-toxicity, naturally occurring anthocyanin is potentially suitable as a colorant for foods and cosmetics. To the wider use of the anthocyanin, the immobilization on the inorganic host for an easy handling as well as the improvement of the stability is required. This study is focused on the adsorption of significant amount of the natural anthocyanin dye onto mesoporous silica, and on the stability enhancement of the anthocyanin by the complexation. The anthocyanin has successfully been adsorbed on the HMS type mesoporous silica containing small amount of aluminum. The amount of the adsorbed anthocyanin has been increased by modifying the pore wall with n -propyl group to make the silica surface hydrophobic. The light fastness of the adsorbed anthocyanin has been improved by making the composite with the HMS samples containing aluminum, although the degree of the improvement is not so large. It has been proposed that incorporation of the anthocyanin molecule deep inside the mesopore is required for the further enhancement of the stability.

Hexagonal BN (h-BN) films codoped with Mg and O atoms were grown on n-type Si and quartz substrates heated at 500 °C by the sputtering of h-BN targets containing MgO. It is confirmed from Fourier transform infrared spectroscopic measurements that h-BN films are formed by sputtering h-BN targets containing 0.25 mol% MgO in an atmosphere of Ar + 1% O 2 . Absorption is seen at wavelengths 2 . The calculated energy levels of defects and impurities of O and Mg indicate that the absorption near 400 nm is originated from nitrogen vacancies, and that the absorption near 220 nm is ascribed to O N –Mg B –O N complexes, where O N and Mg B denote O atoms at N sites and Mg atoms at B sites, respectively. The film prepared from the h-BN target (0.5 mol% MgO) in an Ar atmosphere exhibits a low turn-on electric field of 2.2 V/μm and a gentle slope in the Fowler–Nordheim plots. The gentle slope in the Fowler–Nordheim plots is not ascribed to an increase of a field-enhancement factor, but to a decrease of the work function.

Films have been prepared at substrate temperatures of 125 to 200 °C by chemical vapor deposition. As a substrate temperature decreases, the grain sizes of the films are decreased. From transmission electron microscopic observation, the film grown at 125 °C is found to be constructed from ZnO quantum dots with 5 nm in diameter. Photoluminescence spectra in ultraviolet region at 40 K or less are assigned to both free electron-acceptor and donor-acceptor pair emissions, whereas photoluminescence spectra at temperatures higher than 50 K are due to the free electron-acceptor emission. The peak energy of the free electron-acceptor emission for the film deposited at 125 °C is 0.143 eV larger than that for the film deposited at 200 °C. The blue shift of the emission peak is ascribed to the quantum confinement effect. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Composites of mesoporous SiO2and LiAlCl4were synthesized, and the change in ionic conductivity due to the formation of the composites was investigated. The electrical conductivity of the composite with the SiO2: LiAlCl4of 2 : 3 was the highest with a value of 2 x 10-6S/cm at room temperature. A higher order of conductivity was observed for the composite compared to the non-composite LiAlCl4. In addition, it was found that the conductivity of the composites depends on the pore size of the mesoporous SiO2.

ron fluoride (III) anhydrate fine particle was prepared by drying in vacuum from FeF3·3H2O, a mechanical milling process and a calcination at 473 773 K. Particle size of FeF3·3H2O was ca. 3 5 μm and that of FeF3 anhydrate was 100 500 nm after drying and milling. FeF3 sample only after drying and milling was hygroscopic and became FeF3·3H2O under atmosphere. FeF3 became stable under atmosphere after oxidation at 673 K for more than 20 minutes. It was found that Fe2O3 was produced by calcination and covered the surface of FeF3 particles. In Charge-discharge measurements, the discharge capacity of these FeF3 samples was 150 - 200 mAh/g at a discharge rate of 0.1 C. The oxidation could improve the discharge properties of FeF3 cathode.

A p-type ZnO film was successfully obtained by the alternate deposition of ZnO and Mg3N2 in radio-frequency (RF) magnetron sputtering process. ZnO and Mg3N2 (or Mg-oxynitride) films were alternately deposited on a substrate rotated above ZnO and Mg3N2 targets, where ZnO and Mg3N2-sputtering were carried out at RF power of 30 W and 0–90 W, respectively. In the case of the alternate deposition, where the substrate was kept for 0.2 s above the Mg3N2 target, p-type ZnO films were grown by Mg3N2-sputtering at 50–70 W, whereas an n-type ZnO film was grown at 90 W. The c-axis lengths of the films prepared by Mg3N2-sputtering at 0–50 W increase with RF power, and oppositely the c-axis lengths of the films prepared by Mg3N2-sputtering at 60–90 W decrease with RF power. p-type ZnO films were grown by Mg3N2-sputtering at 50 W for 2 and 5 s, whereas insulative ZnO films were grown by Mg3N2-sputtering at 70 W for 2 and 5 s. The band-gap energies of the p-type ZnO films prepared by Mg3N2-sputtering at 50 W for 0.2 and 5 s are estimated to be 3.31 and 3.39 eV, respectively. The increase of the band-gap energies of the p-type ZnO films is caused by the intermixing of ZnO and Mg-oxynitride films.

Films were deposited on a glass substrates heated at 100 °C by alternate deposition of ZnO and Mg3N2 films in an atmosphere of N2 + 0.2% O2. p-type ZnO films with the resistivity of 9.9×103 - 4.5×103 Ωcm were grown by Mg3N2 sputtering for 0.2 s at 50-70 W, whereas an n-type ZnO film was grown for 0.2 s at 90 W. Appearance of the n-type ZnO film is caused by a decrease of O2-partial pressure in an atmosphere. The contraction of the c-axis due to the incorporation of Mg atoms is found in these p-type and n-type ZnO films. When the Mg3N2-depostion period was extended to 5 s, p-type ZnO films were grown in the alternate sputtering at 50 W, whereas only insulator films were grown in the alternate sputtering at 70 W. The optical band gap of the films increases with both a RF power and a period of Mg3N2-deposition.

The stability of the naturally occurring annatto dye against irradiation with visible light was enhanced by intercalation into octyl trimethylammonium and dodecyl trimethylammonium montmorillonite. The intercalated dye exhibited improved light fastness. The effect of the stability enhancement was more distinct with dodecyl trimethylammonium montmorillonite. The reason of the improvement was proved to be the hindrance from the contact with the atmospheric oxygen because the dye molecules were incorporated in the interlayer space. The amount of the adsorbed dye could be increased more than ten times when an aqueous ethanolic solution was used instead of pure ethanol as solvent in the adsorption process.

Flavylium dye, an analogue of natural anthocyanin, is an expectedly safe coloring material. However, their color instability limits its practical use. We have prepared Fe-containing HMS type mesoporous silicate, and have made a composite of the FeHMS and the flavylium dye. The color stability of the flavylium under visible light irradiation has been enhanced by making the composite with the FeHMS. During 8 h irradiation, 45% of the absorption of the flavylium adsorbed on HMS has been lost, while only 5% of the absorption has been lost on the FeHMS with 2 mol% Fe. From the UV–vis spectra, FeHMS has been confirmed to contain the Fe 3+ species highly dispersed in the silica framework. Since the Fe 3+ species works as an acid site in the mesopore of HMS, the enhancement of the stability has partially been attributed to the solid acidity of the FeHMS. Under strong light irradiation (>800 klx), the degradation rate of the flavylium has been independent of the light irradiance, because the diffusion rate of the oxygen into the mesopore cannot satisfy the demand to oxidize the flavylium dye under irradiation. This means that the inhibition of the contact with the external oxygen also contributes to the stabilization of the flavylium dye incorporated in the mesopore.

Conduction mechanism of Li + cation in a stoichiometric LiInI 4 was studied experimentally. In general, the interpretations of the 7 Li NMR powder spectrum and its temperature dependence are not straightforward because of a broadening due to not only dipole–dipole interactions but quadrupole effect ( 7 Li, I = 3/2). In this NMR experiment on LiInI 4 , the quadrupole effect and the dipole–dipole interactions could be discussed separately using a single crystal. Since LiInI 4 belongs to a monoclinic crystal, two pairs of satellite transitions ( Δm = 3/2 ↔ 1/2 and − 3/2 ↔ − 1/2 ) as well as a central transition ( Δm = − 1/2 ↔ 1/2) were observed for 7 Li NMR due to the first order quadrupole effect. Above 380 K, however, these two satellite pairs merged into one pair associated with the motional narrowing phenomenon. This finding directly suggests a site exchange of the Li + between two crystallographically equivalent sites. The exchange rate ( k ex ) was estimated using a spectrum simulation of the coalescence phenomena and, furthermore, the bulk ionic conductivities were calculated as a function of temperature which agreed well to those from the complex impedance method. The site exchange phenomenon especially appeared on the single crystal NMR spectra was proved to be a good technique to evaluate ionic conductivity and its mechanism in solid.

2-Hydroxychalcones are known to be converted to the colored flavylium form under UV irradiation. In this study, the photochemical conversion of two 2-hydroxychalcone derivatives (4′-dimethylamino-2-hydroxychalcone and 4′-methoxy-2-hydroxychalcone) has been carried out in the solid matrix by the intercalation into the layer of the clay, montmorillonite. The 2-hydroxychalcone has been adsorbed on the clay by modifying the clay interlayer with a cationic surfactant, dodecyltrimethylammonium chloride. The addition of an acidic compound (benzenesulfonic acid) has induced the successful coloring reaction of the 2-hydroxychalcone derivatives by the conversion to the flavylium under UV irradiation between the clay interlayer. A delayed coloration has been observed on the short time irradiation of 4′-methoxy-2-hydroxychalcone included in the clay layer.

The iron oxide/polyaniline electrode was prepared from the photoanodic deposition of polyaniline film on the iron oxide electrode. The two linear relations of Mott-Schottky plots were obtained on the iron oxide/polyaniline electrode in HClO4 aqueous solution. This electrode showed a stable photoanodic current under visible light irradiation and also a linear dependence of photoanodic current on glycolic acid concentration.

We have enhanced the stability of a flavylium dye, a model compound of a natural anthocyanin dye, by the incorporation into the interlayer of a natural clay, bentonite. The composite of the flavylium and the bentonite shows excellent stability under increased temperature (up to 353 K) or alkaline environment (pH ∼ 9) compared to the original flavylium dyes. This material can be candidate of an environmentally friendly coloring material. Increased amount of dye causes a muddy color due to the formation of dye aggregate. Samples with brilliant color can be obtained with the loading amount less than 0.25 mmol dye per g-clay.

The aim of this study is the improvement of the photostability of several natural anionic dyes, carmine (CM), carthamus yellow (CY), and annatto dye (ANA), by complexation with hydrotalcite. The composite of the dyes and hydrotalcite is prepared by the coprecipitation method. CM is successfully intercalated in the hydrotalcite layer when the amount of introduced CM is large. The photostability of CM in CM/HT composites is superior to the CM adsorbed on silica surface. The effect of the stability enhancement is larger when the amount of introduced CM exceeds 0.23 g/g-host, or when the layer charge density of the hydrotalcite is larger. CY is also stabilized by complexation with hydrotalcite, whereas ANA is not stabilized by complexation with hydrotalcite. The photostability of an anionic natural dye can be improved by intercalation into the hydrotalcite layer, if the dye has a hydrophilic nature and a rather planar structure. The intercalated dye is stabilized by the protection from the attack of the atmospheric oxygen. In addition, contribution of the electrostatic interaction between the positively charged hydrotalcite layer and the intercalated anionic dye is also proposed.

The iron oxide electrode was prepared from thermal oxidation of iron at 600 °C for 3 h in air atmosphere. This electrode with the structure of Fe 3 O 4 and α-Fe 2 O 3 showed the response of photoanodic current to the light with wavelength shorter than 600 nm. The band gap energy of this electrode was 1.99 eV. The onset potential of distinct steady photocurrent and also the flatband potential were 0.80 and 0.09 V vs. Ag/AgCl, respectively, in 0.1 M HNO 3 aqueous solution. The cell consisting of the iron oxide photoanode in HNO 3 –Pb(NO 3 ) 2 and the graphite cathode in H 2 SO 4 –Ce(SO 4 ) 2 caused the PbO 2 deposit on the surface of the former electrode due to visible light irradiation without application of voltage. By holding the potential of this electrode at more positive value than 0.90 V, the photoanodic removal rate of Pb 2+ in HNO 3 –Pb(NO 3 ) 2 solution was higher than that observed when Ce 4+ was used as electron acceptor.

Because of its non-toxicity, naturally occurring anthocyanin has a potential for the utilization as a harmless coloring material. Its color instability under alkaline condition or light irradiation limits its practical use. Anthocyanin can be stabilized by the intercalation into montmorillonite. The anthocyanin–montmorillonite maintains the original color at basic condition of even pH 11. The intercalated anthocyanin also exhibits enhanced stability against visible light irradiation compared with the anthocyanin simply adsorbed on the external surface of the mineral particles. The stability enhancement is attributed to the electrostatic host–guest interaction and to steric protection from the attack of atmospheric oxygen. The intercalated complex can be a candidate of an environmentally friendly coloring material.

Li 3 InBr 6 − x Cl x was synthesized and the substitution effect on conductivity was investigated. Li 3 InBr 6 − x Cl x was single phase at all compositions. The volume of crystal lattice was decreased with Cl content and the rate of the decrease changed at x = 3. The conductivity of Li 3 InBr 6 − x Cl x had a maximum in Li 3 InBr 3 Cl 3 and its value was 1.2 × 10 −4 Scm − 1 at 300 K. The activation energy of the conduction was at the minimum around x = 3 and its value was 20 kJ mol − 1 . Phase transition temperature was lowered to be 285 K and the high conduction phase was stabilized by substitution Br with Cl. 7 Li NMR spectra in Li 3 InBr 3 Cl 3 was sharp and it was confirmed that the diffusion of Li ion was fast at room temperature.

Undoped and Li-doped NiO films have been prepared by radio frequency sputtering and electron-beam evaporation techniques. These sputtered films prepared at a lower pressure of 2.6 × 10 − 1 Pa show no diffraction peaks and their surfaces are smooth. These films are p-type semiconductors and their resistivity is dependent on an O 2 -partial pressure. A minimum resistivity of 0.39 Ω cm is attained for a Li-doped NiO film prepared at RF power of 20 W in 50% O 2 atmosphere. In contrast, Li-doped NiO films prepared by electron-beam evaporation exhibit no diffraction peaks, but their surface is not smooth. The fabrication of pn-junction is carried out between NiO films and amorphous n-type transparent oxide films, e.g., In–Zn–O and In–Ga–Zn–O. No rectification characteristic is seen at an interface of In–Zn–O and Li-doped NiO films, while the rectification characteristic is achieved in In–Zn–O/In–Ga–Zn–O/NiO/Au device. The threshold voltage of 2.3 V is estimated from the current vs. voltage characteristic.

ZnO films codoped with Al and N have been prepared by radio frequency magnetron sputtering in an Ar atmosphere, using targets of mixtures of ZnO and AlN powders. The Al-doped ZnO films are transparent, whereas the films codoped with Al and N are colored. The Al- and N-concentrations in the colored films are estimated to be 4–7 at.% and 1–2 at.%, respectively. No enhancement of the carrier density is seen in the colored ZnO films, whereas the colored films exhibit lower etching rates of 3–5 nm/s in a 0.1 M HCl solution, in comparison with the Al-doped ZnO films. For the colored film, the anisotropic grain growth occurs, and cubic grains are produced after etching. The low etching rates of the colored films are ascribed to the epitaxial growth of AlN films on the surfaces of ZnO grains, rather than the incorporation of Al–N and Al–O bonds into the ZnO lattice.

ZnO films prepared from the ZnO target containing 2% AlN are transparent irrespective of radio frequency (RF) power. The obtained ZnO films have the carrier density of 3.8 × 1020 cm−3 or less and the low mobility of 5.3–7.8 cm2/(V s). In the case of 5% AlN target, ZnO films prepared at 40, 60 and 80 W are transparent, whereas ZnO films prepared at 100 and 120 W are colored. As RF power increases from 40 to 120 W, the carrier density increases straightforwardly up to 5.5 × 1020 cm−3 at 100 W and is oppositely reduced to 3.2 × 1020 cm−3 at 120 W. In the case of 10% AlN target, ZnO films prepared at 60 W or more are colored, and have the carrier density of 4 × 1020 cm−3 or less. The N-concentration in these colored films is estimated to be 1% or less. The Al-concentration in the ZnO films prepared from the 5 and 10% AlN targets is higher than 2%. The carrier density of the ZnO films containing Al and N atoms is nearly equal to that of ZnO films doped with Al atoms alone. There is no evidence in supporting the enhancement of the carrier density via the formation of N-AlxZn4−x clusters (4 ≥ x ≥ 2).

We have enhanced the stability of some derivatives of a flavylium dye, a model compound of a natural anthocyanin dye, by incorporating them between the interlayer of a clay mineral, montmorillonite K10. The incorporation procedure is simply mixing the solution of the flavylium dyes with the clay powder. The resulting colored powder shows excellent stability under increased temperature (up to 353 K), alkaline environment (pH ∼ 9), and visible light irradiation, compared to the original flavylium dyes. This material can be a candidate for an environmentally friendly coloring material.

ZnO films doped with Li and Cl atoms have been prepared by organometallic chemical vapor deposition method. In photoluminescence spectra of the doped ZnO films, strong emission appears at 376 nm which is slightly longer than that of free-excitons. As excitation intensity increases, a peak wavelength of the emission is shifted toward a shorter value. The emission near band-gap edge is assigned to radiative recombination via Li-Cl pairs.

Li3-2xMxInBr6 (M=Mg, Ca, Sr and Ba) and Li3In1-xMxBr6 was synthesized, and thier substitution effect was investigated by means of 7Li and 115In NMR, X-ray diffraction and AC conductivity measurements. Phase transition was observed at 314 K in Li3InBr6 and fast Li+ diffusion was observed in the high temperature phase. Li3InBr6 has high Li+ ion conductivity and showed a little difference in X-ray diffraction patterns between the low-temperature phase and the high-temperature phase. These indicate that the sub-lattice for Li+ ions changed largely at the phase transition point and this change makes Li+ diffusion easily. In the high temperature phase of substituted compounds, the conductivity decreased with the amounts of substitution. and defects produced by the substitution with divalent cation did not contribute to the Li+ ion conduction. In the LT phase for Mg compound, the ionic conductivity increases up to x = 0.4 due to the introduction of the extrinsic vacancies.

Stearic acid films have been deposited on single crystalline TiO 2 (1 1 0) substrates by vacuum evaporation. No changes are seen in AFM topographic images of the stearic acid films after the scan at a bias voltage of -10 to 10 V in the dark. Similarly, ultraviolet irradiation at a bias voltage

Nano-scale Cu metal patterning was achieved by the use of an atomic force microscope. When the scanning with the cantilever of atomic force microscope (AFM) covered with the solid electrolyte was carried at a negative voltage, the Cu metal was deposited on TiO 2 substrates. The Cu metal on TiO 2 , a glass and Si substrates was absorbed at the positive voltage. The deposition and the absorption of Cu could be repeated and carried out at room temperature without a specific treatment. The letters “Y” and “T” were written with 50 nm resolution by the scanning. The reaction between the tip of the cantilever and substrate is a simple electrochemical reaction.

ZnO films containing both Be and N atoms were deposited on (0001)-sapphire substrates heated at 250 °C, by using a target consisting of Be sheets placed on ZnO powders. There are only ZnO (0002) peaks observed in the X-ray diffraction (XRD) patterns of the ZnO films. As the power of radio frequency (RF) in sputtering increases, the c-axis lengths of the sputtered ZnO films decrease significantly, and the concentration of Be atoms in the ZnO films increases remarkably. The presence of Be and N atoms is confirmed in the ZnO film prepared at 70 W, from X-ray photoelectron spectroscopic (XPS) measurements. For the ZnO film prepared at 70 W, the binding energy of Be 1s and of N 1s is evaluated to be 114.0 and 398 eV, respectively. The concentration of N atoms is as low as 1% for the ZnO film containing no Be atoms, whereas the high concentration of 7% N atoms is attained in the ZnO film containing 4% Be atoms. The ZnO films prepared at 120 W or more are insulators, and the ZnO film doped with N atoms alone is an n-type semiconductor. The ZnO film containing both 4% Be and 7% N atoms is a p-type semiconductor with a resistivity of 45 Ω cm.