IIN Frontiers in Nanotechnology Seminar Series – Taeghwan Hyeon
Chemistry for Nano, and Nano for Medicine & Energy
Over the last 10 years, our laboratory has focused on the designed chemical synthesis and applications of uniform-sized nanocrystals. In particular, we developed a novel generalized procedure called as the “heat-up process” for the direct synthesis of uniform-sized nanocrystals of many metals, oxides, and chalcogenides. This heat-up process is now popularly used by many scientists in synthesizing various uniform-sized nanocrystals.
Recently our group has been focused on medical applications of various uniform-sized nanoparticles. For example, using 3 nm-sized iron oxide nanoparticles, new non-toxic MRI contrast agent was realized for high resolution MRI of blood vessels down to 0.2 mm. We demonstrated that ceria nanoparticles protect against ischemic stroke in an in vivo animal model. We reported the first successful demonstration of high-resolution in vivo three-photon imaging using biocompatible and bright Mn2+ doped ZnS nanocrystals. We fabricated tumor pH-sensitive magnetic nanogrenades composed of self-assembled iron oxide nanoparticles and pH-responsive ligands for theranostic applications.
We reported the large-scale synthesis of magnetite nanocrystals imbedded in a carbon matrix and hollow iron oxide nanoparticles. We demonstrate galvanic replacement reactions in metal oxide nanocrystals. When Mn3O4 nanocrystals were reacted with iron(II) perchlorate, hollow box-shaped nanocrystals of Mn3O4/γ-Fe2O3 (“nanoboxes”) were produced. These iron oxide-based nanomaterials exhibited very high specific capacity and good cyclability for lithium ion battery anodes.