Nanoparticle assemblies: dimensional transformation of nanomaterials and scalability.

Integration of nanoparticles (NPs) and other nanomaterials with existing technologies must take place in order to substantially widen the spectrum of their applications. This task can be simplified by taking advantage of NP assemblies provided that they retain the unique properties of nanomaterials in organized systems of larger dimensions. There is a large variety of methods of assembling NPs into superstructures containing 10-10(10) particles that include field-, bio-, and interface-directed techniques as well as self-organization. Some of them can traverse the scales from typical lengths of 10(-9) m (nano) to 10(-5) m (micro) and 10(1) m (macro) conducive to other technologies. Such dimensional transformation of nanomaterials makes possible utilization of well-established processing techniques, and hardware tools operating at these scales. Therefore, answering the question "What types of the assembly techniques are suitable for such a task?" is vital for the future application of nanoscale materials in any field of use. These techniques must result in organized structures of at least 5 × 10(-7) m in size, offer relative simplicity and fault tolerance. This review focuses on the recent development of NP assembly techniques that have the possibility of satisfying these requirements. The expected applications and future developments are also discussed.