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.

Several nm thick ZIF-8 nanosheets can be synthesized from multiple hydrophilic precursors in the hydrophilic space inside bilayers in a decane solution of the amphiphile Brij L4.

Zeolites catalyze some reactions in their molecular‐sized pores, but large molecules can react only on their external surface. Zeolite‐nanosheets (NSs) have been developed as catalysts for large molecules. The previously reported methods to synthesize zeolite‐NSs are specialized for each zeolite type. Here we propose a new method to synthesize various zeolite‐NSs from the same amorphous aluminosilicate NSs (AAS‐NSs) as a universal precursor. We successfully synthesized the unprecedented AAS‐NSs in the hydrophilic space of the stable hyperswollen lyotropic lamellar (HL) phase. The four zeolite types could be obtained from the single‐species AAS‐NSs. These results imply that this method enables us to synthesize almost all types of zeolite‐NSs. Moreover, the synthesized CHA‐NSs have great potential for various applications because of their thickness and large external surface area.

Zeolites catalyze some reactions in their molecular-sized pores, but large molecules can react only on their external surface. Zeolite-nanosheets (NSs) have been developed as catalysts for large molecules. The previously reported methods to synthesize zeolite-NSs are specialized for each zeolite type. Here we propose a new method to synthesize various zeolite-NSs from the same amorphous aluminosilicate NSs (AAS-NSs) as a universal precursor. We successfully synthesized the unprecedented AAS-NSs in the hydrophilic space of the stable hyperswollen lyotropic lamellar (HL) phase. The four zeolite types could be obtained from the single-species AAS-NSs. These results imply that this method enables us to synthesize almost all types of zeolite-NSs. Moreover, the synthesized CHA-NSs have great potential for various applications because of their thickness and large external surface area.