Forming nanomaterials as layered functional structures toward materials nanoarchitectonics

Abstract

Although progress in nanotechnology is anticipated to stimulate the development of innovative materials, the areas of nanotechnology and materials science are somehow separated with little common ground in current technologies. Nanotechnology has some analytical aspects that are beneficial mainly to the nanoscopic sciences at the atom or molecular levels. Experience of these advanced techniques has only been applied in synthetic approaches to macroscopic materials in rather immature level. Forming nanomaterials into hierarchic and organized structures is a rational way of preparing advanced functional materials. Recently, one of us coined the term materials' nanoarchitectonics to express this innovation. This review focuses on recent research to develop functional materials by forming nanomaterials into organized structures, especially in well-ordered layered structural motifs. This layered nanoarchitectonics can be achieved by using the versatile technology of layer-by-layer assembly. Reassembly of bulk materials into novel layered structures through layered nanoarchitectonics has created many innovative functional materials in a wide variety of fields as can be seen in ferromagnetic nanosheets, sensors, flame-retardant coatings, transparent conductors, electrodes and transistors, walking devices, drug release surfaces, targeting drug carriers and cell culturing.

Emerging pressure-release materials for drug delivery

“…Such regulation of host--guest interactions using mechanical force has not been frequently reported prior to the example based on a cyclodextrin gel. Applying this new concept to other materials systems including mesoporous materials [15] and layer-by-layer films [16] is expected to lead to various methods for pressure-induced drug release. Hand manipulation for drug delivery for use in any situation will thus be realized.…”

Paradigm shift from self-assembly to commanded assembly of functional materials: recent examples in porphyrin/fullerene supramolecular systems

“…Functional units should be fixed with the required thickness and orientation only at the required positions, which must be controlled under external commands. In addition to the SAM strategy, Langmuir-Blodgett (LB) [100,101] and LbL assembly [102,103] techniques have been widely used for thin-film assemblies of various functional units, some of which are not available for vapor deposition methods under high vacuum. The SAM technique can be applied to a wider range of substances, but it is not a useful method for multilayer fabrication.…”

From Nanotechnology to Nanoarchitectonics

“…It is expedient to embark on the next phase of nanotechnology, which is Nanoarchitectonics. This terminology and its concept were first proposed by Dr. Masakazu Aono at the 1st International Symposium on Nanoarchitectonics Using Suprainteractions in 2000 in Tsukuba, Japan [2,3]. Actually, the 21st century started with Nanoarchitectonics.…”