Preparation of Ordered Nanoparticle-Array Based on Dissipative Structures

Masatsugu SHIMOMURA, Tetsuro SAWADAISHI

Research Institute for Electronic Science, Hokkaido University, Frontier
Research System, RIKEN Institute

We have found that regularly arranged mesoscopic polymer patterns are spontaneously prepared by simple casting of highly diluted polymer solutions. The driving force of the pattern formation is freezing of dissipative structures, such as Benard convection and fingering instability, dynamically formed in the cast polymer solution. Because of its physical generality, the pattern formation based on the dissipative structures can be applied for any materials. Several kinds of nanoparticles are employed for 2-D patterning by using dissipative structures since ordered colloidal assemblies of nanoparticles are applicable for photonics and sensing devices. Regularly arrayed stripes of nanoparticle aggregates were formed when highly diluted water dispersions were cast on fleshly cleaved mica surface. The close up view of the stripe by a scanning electron microscope clearly showed monolayer deposition of the silica particles with hexagonal packing on the substrate.