Inorganic/organic hybrid ultrathin films of MoS2 and a cationic amphiphile, dihexadecyldimethylammonium bromide (DHA+Br-), were prepared using the Langmuir−Blodgett (LB) technique. The surface pressure−area isotherms of DHA+Br- changed by introducing exfoliated MoS2 particles into the subphase. On the other hand, the isotherms of icosanoic acid in the presence and absence of MoS2 particles in the subphase were essentially the same. The UV/vis reflection spectra of DHA+(Br-) monolayers on MoS2 suspension showed a broad absorption band assignable to MoS2, whereas that of icosanoic acid did not show any appreciable band. These results suggest the formation of hybrid monolayers consisting of DHA+ and MoS2. The hybrid monolayers were transferred successfully onto substrates using a horizontal lifting method to form LB films. That was confirmed by the infrared and UV/vis absorption spectroscopies and AFM, although the transfer ratios were not determined. The X-ray diffraction patterns of the LB films showed the layered structure in which organic and inorganic sheets are stacked alternately. The AFM image of a single-layer LB film of DHA+ and MoS2 showed flat, plate-like particles with diameters in the submicrometer region. The structure of the hybrid LB films depended strongly on the MoS2 concentration in the subphase for the preparation of the hybrid monolayers. The number of DHA+ molecules per unit area of the LB film increased with increasing MoS2 concentration in the subphase while the amount of MoS2 in the LB film remained unchanged. Further, the tilt angle of the hydrocarbons of DHA+ was large and the interlayer spacing of the LB film was small when the MoS2 concentration in the subphase was large. A model of the formation of the hybrid film was proposed.

II nn ss tt rr uu cc tt ii oo nn ss ff oo rr uu ss e ABSTRACT In this study, anatase crystalline TiO 2 mesoporous films were was formed by anodizing of titanium specimens without annealing procedures. The specimens were anodized at 3 and 20 V in 0.6 mol dm −3 K 2 HPO 4 and 0.2 mol dm −3 K 3 PO 4 /glycerol electrolyte at 433 K. The obtained films had mesoporous structures with pore diameters as small as ~10 nm. The mesoporous film formed at 20 V without annealing (MP-20V) was a mixture of amorphous phase and nanograined anatase, which clearly showed strong <001> preferred orientation, whereas that at 3 V was completely amorphous. Even without annealing, the MP-20V showed high photocatalytic activities for decomposition of water and methylene blue. In contrast, the anodic TiO 2 nanotube film formed in NH 4 F/ethylene glycol electrolyte revealed photocatalytic activities only after annealing at 723 K, because of the amorphous nature of the as-anodized nanotube film. The MP-20V film also showed superhydrophilicity with UV light irradiation. 3

We report the size-selective photocatalytic decomposition of organic molecules using crystalline anodic TiO2 nanochannel films as the photocatalyst. The porous TiO2 films were formed by anodizing titanium at 20 V in glycerol electrolyte containing various amounts of K3PO4, K2HPO4, and KH2PO4 at 433K. Regardless of the electrolyte composition, the as-formed TiO2 films had a crystalline anatase structure. The basicity of the electrolyte markedly influenced the morphology of the TiO2 nanochannel films; more regular nanochannels developed with increasing basicity of the electrolyte. Because the diameter of the nanochannels in the films formed in a basic electrolyte was as small as similar to 10 nm, the anodic TiO2 nanochannel films with a thickness of 5 mu m revealed a selective photocatalytic decomposition of methylene blue (MB) in a mixture of MB and direct red 80 (DR) kept under UV irradiation. The importance of the diameter of the nanochannels and their uniformity for size-selective decomposition of organic molecules were investigated

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A metallic titanium and zirconium micro-porous alloy for electrolytic capacitor applications was produced by electroless reduction with a calcium reductant in calcium chloride molten salt at 1173 K. Mixed TiO 2 -70at%ZrO 2 oxides, metallic calcium, and calcium chloride were placed in a titanium crucible and heated under argon atmosphere to reduce the oxides with the calcium reductant. A metallic Ti-Zr alloy was obtained by electroless reduction in the presence of excess calcium reductant and showed a micro-porous morphology due to the sintering of each of the reduced particles during the reduction. The residual oxygen content and surface area of the reduced Ti-Zr alloy decreased over time during the electroless reduction. The element distributions were slightly different at the positions of the alloy and were in the composition range of Ti-69.3 at% to 74.3 at%Zr. A micro-porous Ti-Zr alloy with low oxygen content (0.20 wt%) and large surface area (0.55 m 2 g -1 ) was successfully fabricated by electroless reduction under optimal conditions. The reduction mechanisms of the mixed and pure oxides by the calcium reductant are also discussed.