Chemistry of Materials Nanoarchitectonics for Two-Dimensional Films: Langmuir–Blodgett, Layer-by-Layer Assembly, and Newcomers

Considering the creation of functional materials based on nanoscience, an emerging concept of nanoarchitectonics has been proposed to combine nanotechnology with other material-related fields. Nanoarchitectonics aims to establish universal methodologies to architect functional materials using nanounits of atoms, molecules, and nanomaterials. The ultimate goal of nanoarchitectonics is to construct high-performance functional materials, as seen for those in biological systems. Functional molecules in biological systems are rationally integrated, mostly on the basis of various membrane structures. With this in mind, this review discusses materials nanoarchitectonics for two-dimensional films. As major methods, the Langmuir–Blodgett (LB) method and the layer-by-layer (LbL) assembly are first focused. The standard LB method for various materials and technical extensions of the LB method are initially discussed, and then the LbL assembly with certain advances is described. After that, some examples of other advanced two-dimensional techniques for materials creation are presented. Although standard methodologies have long histories (more than 100 years for LB and 30 years for LbL), their developments are still active using out of common sense conditions and introducing emerging nanomaterials. Especially, this paper demonstrates that out-of-box thinking will lead to the development of new thin film nanoarchitectonics.