Advanced Colloids Experiment-Microscopy-3 (ACE-M-3)

The Advanced Colloids Experiment-Microscopy-3 (ACE-M-3) experiment involves the design and assembly of complex three-dimensional structures from small particles suspended within a fluid medium. These so-called “self-assembled colloidal structures,” are vital to the design of advanced optical materials. In the microgravity environment, insight will be provided into the relation between particle shape, crystal symmetry, and structure: a fundamental issue in condensed matter science.

The experiment has concluded, and science is being evaluated.

New functional materials can, in principle, be created using small particles (called colloids) that self-assemble into a desired structure by means of a recognition and binding scheme. The Advanced Colloids Experiment-Microscopy-3 (ACE-M-3) experiments utilize optical microscopy for time- and space-resolved imaging of a particular non-spherical colloid, whose condensed (solid-like) phase can be controlled by adding ‘depletants’. These smaller particles allow the tuning of the interactions between the colloids, and in this way control the structure of the colloidal dispersion.

Ultimately, the ability to design colloidal particles with a variety of well-controlled three-dimensional bonding symmetries opens a wide spectrum of new structures for colloidal self-assembly, beyond particle assemblies whose structures are defined primarily by repulsive interactions and shape. Such materials might include photonic crystals with programmed distributions of defects. Optical technology utilizing such materials may offer intriguing solutions to unavoidable heat generation and bandwidth limitations facing the computer industry.

Microgravity aids self-assembly and motility on materials that have different densities. The work in ACE-M-3 will lay the foundation for the understanding of this process.

Space Station Research Explorer