From small molecules to entire organisms, evolution has refined biological structures at the nanoscale, microscale and macroscale to be chiral—that is, mirror dissymmetric. Chiral nanoscale materials can be designed that mimic, refine and advance biological chiral geometries, to engineer optical, physical and chemical properties for applications in photonics, sensing, catalysis and biomedicine. The idea that inorganic materials can be chiral seems to be counterintuitive. In this talk, I will discuss about a new mechanism that can generate chiral nanomaterials based on the interaction between chiral peptides and high index plane of metal surface. The enantioselective interaction of chiral molecules and high-Miller-index facets can break the mirror symmetry of the metal nanocrystals. I will also discuss about interesting optical properties of these chiral gold plasmonic nanoparticles that was synthesized by the peptides and amino acid. The resulting 432 symmetric chiral morphology result in the highest dissymmetry factor (g) and the efficient coupling with other materials. I believe that this synthetic approach for the chirality control of inorganic nanomaterials can have a lot of potential to maximize the light-matter interaction, resulting in many optical, electronic and biological applications.
Reference)
“Enantioselective Sensing by Collective Circular Dichroism,” Nature. 2022, 612, 470.
“Amino-Acid- and Peptide-Directed Synthesis of Chiral Plasmonic Gold Nanoparticles,” Nature. 2018, 556, 360.

Professor Ki Tae Nam received his B.S. and M.S. in Materials Science and Engineering from Seoul National University, and his Ph.D. in Materials Science and Engineering from MIT. He got the “outstanding PhD thesis award” from MIT. His PhD thesis was about the “virus-based battery” that has been highlighted as the first demonstration of virus based electrochemical devices. During his postdoc (2007-2010) at Lawrence Berkeley National Lab, he studied peptide mimetic polymer to assemble two dimensional structures. Since 2010, His group at SNU continue to pioneer the research area of bioinspired material science to make new functional materials for energy and optical applications. Recent innovations include the development of CO2 utilization chemistry (Nature Energy. 2021, 6, 733 and Nature synthesis. 2024, 3 etc) and the peptide based synthesis of chiral nanomaterials (Nature 2018, Nature 2022 and Nature Materials 2024). In 2022, He received the POSCO Chung-am Award that is one of the most prestigious award in Korea. He is an associate editor for Nano Letters and will serve as one of the chair in MRS Fall 2027 Meeting.