A mesoporous Sn anode was electrodeposited in the presence of lyotropic liquid crystals made of nonionic surfactants. The introduction of mesoporous structure was effective for the accommodation of volume change of Sn during charge and discharge cycling of Li ions. The discharge capacity of the mesoporous Sn anode at 1 C rate was as high as 425 mA h g À1 at the 100th cycle, and that was as high as 320 mA h g À1 at the 100th cycle even though at 5 C rate.There is a strong incentive to develop and characterize noncarbonaceous materials for use as anodes for lithium ion secondary batteries that deliver higher capacities than carbon. A Sn anode has been reported to have higher theoretical capacity (994 mA h g À1 ) than that of carbon (372 mA h g À1 ).1 However, the Sn anode has a problem that its cycle life is unsatisfactory because of Sn disintegration due to the volume change during the charge and discharge cycling of Li ions. To solve this problem, Sn-based alloys with inactive elements against lithium such as Ni 2 have been investigated. Recently, an amorphous ternary Sn-Co-C anode has been introduced to a practical use. 3Many mesoporous materials with specific structural features (e.g., uniform mesopore size and high surface area) have extensively been investigated. In particular, mesoporous metals with high electroconductivity are very promising for various electrochemical applications. Since the first report by Attard et al.,4 several mesoporous metals including Sn 5 have been prepared by the reduction of the corresponding metal ions in the presence of lyotropic liquid crystals (LLC) made of nonionic surfactants. 6 The mesoporous metals have been mainly prepared by electrodeposition for the reduction of metal ions to form thin films on conductive substrates.In the present study, we prepared mesoporous Sn from LLC and investigated its cycle and rate properties as an anode for lithium ion secondary batteries. The mesoporous structure should suppress the influence of the volume change during the charge and discharge cycling of Li ions, leading to a longer life. Also, the mesoporous structure with high surface area can provide a low diffusion resistance of Li ions into the electrode, which should contribute to an increase of the reaction rate.Mesoporous Sn was prepared on a copper foil by electrodeposition. LLC including Sn ions was prepared by mixing 0.300 g of nonionic surfactant, octaethyleneglycol monohexadecyl ether (C 16 EO 8 ), and an aqueous Sn solution (0.300 g) which was prepared by dissolving both 1.69 g of SnCl 2 . 2H 2 O and 9.15 g of H 2 SO 4 aq. (18.3 mol/L) into water and fixing the volume to 50 mL. The LLC takes a 2D-hexagonal symmetry, as is confirmed by low-angle XRD analysis. The electrodeposition was carried out at room temperature and H 2 O-saturated atmosphere with a constant voltage of À100 mV till the current of 1.5 C/ cm 2 was passed. Sn plate was used as the counter electrode. Cycle properties were evaluated using conventional glass cells with two pieces of lithium foil as counter and r...

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Hydrogels have become popular as drug carriers. Controlled release of the drugs from hydrogels can reduce dosage, inducing prevention of side effects. However, the hydrophilicity of hydrogels interferes with controlled release of hydrophobic drugs such as anticancer agents or antibiotics. In this study, we developed hydrophobically-modified gelatin (HMG) hydrogel, which was cross-linked only by hydrophobic interaction. HMG does not require toxic chemical cross-linkers to form hydrogel. In addition, the HMG hydrogel has hydrophobic chambers in its structure which hydrophobic drugs can adsorb to and desorb from. In order to control the amount of hydrophobic drugs adsorbed into the hydrogel, hydrophobic alkyl chains with different lengths (C4-C12) were incorporated into gelatin molecules. Uranine was used as a model for hydrophobic drugs. The adsorption test exhibited that the amount of uranine adsorbed in HMG hydrogels could be controlled by varying hydrophobic alkyl chain length and that the drug could be released in a controlled manner. These results show that HMG hydrogels are promising carriers of hydrophobic drugs.

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