A self-assembling dendritic reactor: versatile formation of characteristic patterns with nanoscale dimension

Abstract

Spherical dendrimers with phenylazomethine backbones are modified onto atomically flat mica or graphite substrates with a simple solvent based spin-coating method, and the resulting surfaces are observed by atomic force microscopy. Especially on the mica substrate, dendrimers form very fine and highly regular patterns with aligned nano-dot arrays and lines. An important observation is that the interval of each dot or line is ≈400 nm whereas previously reported self-assembling patterns exhibit longer intervals than 5 μm. It is revealed that spherical dendrimers with relatively low intermolecular interactions without any terminal modifications are suitable for the fine self-assembling pattern formation. This fact suggests that the regular pattern arises from a physical dissipative structure formation due to a fingering instability induced by Marangoni convection but not by anisotropic intermolecular interactions.

Keywords: dendrimers; nanoscale; patterning; reactors; self-assembly.