The nanosheets of highly symmetric materials with a facecentered cubic lattice such as gold have been synthesized by adsorbing the precursors on a flat surface, whose chemical specificity induces the anisotropy of growth rates. We have succeeded in the fabrication of gold nanosheets in a hydrophilic space inside highly separated bilayers, which work as two-dimensional hydrophilic reactors, in a hyperswollen lamellar liquid crystalline phase of an amphiphile solution. One of the physical properties, amphiphilicity, confines the ingredients therein. The nanosheets can only grow in the in-plane direction due to the inhibition of the out-of-plane growth rather than the anisotropy of growth rates probably. Thus, the synthesis can be accelerated; the particles can be completed within 15 min. As not relying on chemical specificity, silver nanosheets could also be synthesized in the same way. The suspension of gold and silver nanosheets without any amphiphiles could be obtained, and the solvent is replaceable. We found that the width of the obtained gold nanosheets is proportional to the Reynolds number of the solution because the area of the bilayer in the hyperswollen lamellar phase depends on shear stress. This implies that the areas of gold nanosheets depend on the areas of the bilayers, and it can be controlled by changing the Reynolds number. This method could be widely used to continuously obtain large-area nanosheets of various materials in a roll-to-roll manufacturing process.

Silylated ionic liquid (IL)-derived organosilica membrane was formed on porous Al2O3 substrate by the sol-gel method. The permeation and separation characteristics for a binary toluene/CH4 mixture were studied at various temperatures. The membrane showed selective permeation of toluene against CH4 at high temperature up to 170 °C, and stably separated toluene from CH4 at 150 °C for 3 h. The permselectivity was strongly controlled by the affinity of the permeate molecules toward the IL. The results showed that the silylated IL-derived organosilica membrane is promising for selective recovery of aromatic hydrocarbons from CH4. ATR-IR, N2 adsorption and nanopermporometry were performed to evaluate the microstructure and permeation mechanism of the organosilica membrane. These characterizations revealed that the membrane depended on two permeation pathways, "only the dense IL regions" and "organosilica network-derived micropores dense IL regions." The organosilica membrane contained about 1 nm-sized pores, and the contributions of two permeation pathways to gas permeation were successfully evaluated.

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