Colloids and Self-Assembly
We are interested in creating new colloids in chemical methods -including block copolymer particles, rods, clusters, patchy particles- and assembling them into new nanostructures for various applications (photonic crystals, metamaterials, sensors and so on) with surface modification with stabilizer or interactive molecules such as DNA or protein. In addition, based on sol-gel chemistry, we study porous materials for colorimetric sensor or thin-film transistors (oxide semiconductor).
Colloidal particles have been used as model system for atomic structures as well as building blocks for photonic crystals. Our main research interests are in the synthesis of new colloidal particles and their structures by self-assembly. Using particles prepared in our group, we are developing e-paper display, composite film for flexible display, strong light-scattering particles for display or cosmetic applications.
Most of meta-materials have been fabricated by conventional lithographic techniques or top-down approaches. Therefore, it has been very difficult to fabricate meta-structures for visible light, which requires smaller building blocks at least than λ/5 (~100nm). Recently, we have firstly developed a generic route to the synthesis of the perfectly spherical gold nanoparticles, which can be a building block for visible meta-structure. The hybridization of DNA nanotechnology can make the super-spherical gold nanoparticle assembled into meta-structures with a precisely controlled complexity.
Using colloidal particles or micelles as templates, macro- or mesoporous particles could be prepared which is now investigated as efficient host materials for drug delivery or colorimetric sensor dye. With the collaboration with other groups, we are also developing better energy device (Li-ion battery or Solar Cells)
Based on sol-gel chemistry, we have developed solution process for next-generation thin-film transistors (Oxide semiconductor, IGZO), which would be utilized for flexible display. Molecular self-assembly have been investigated for organic or inorganic TFT devices.