ORGS1-0545
Colloidal cubic diamonds from binary Laves phases
Topic
GS1. Graduate Student Oral Session I: Colloidal and Interfacial Polymer Science
When and Where
Sep 28, 2026
14:36 - 14:48
Room 101
Session Chairs
Yoon-Ho HWANG
Jang-Hwan KIM
Hyosung AN
Presenter(s)
Jong-Hoon Kim (Pohang University of Science and Technology (POSTECH))
Co-Author(s)
Abstract
Colloidal self-assembly presents a versatile bottom-up approach for the fabrication of complex three-dimensional architectures, including photonic crystals with tailored bandgap properties. Among various lattice geometries, the diamond structure holds significant promise for achieving wide photonic bandgaps even with moderate refractive index contrasts. However, its inherent mechanical stability of diamond structure poses a considerable challenge for direct colloidal self-assembly and subsequent stabilization. Herein, we report a strategy for the fabrication of a free-standing diamond lattice composed of submicron-sized TiO₂ colloids. This was achieved through the self-assembly of a laves phase, wherein the target diamond network was structurally supported by an interpenetrating pyrochlore framework. Subsequent removal of pyrochlore lattice by thermal treatment realizes the direct diamond lattice. Photonic bandgap calculation of such structure predict the presence of a significant photonic bandgap in the mid-infrared spectral region, highlighting the potential of this approach for the creation of advanced photonic materials. Finally, reflectance measurements of the anatase TiO₂ diamond structure revealed a spectral region similar with the predictions from our calculations.
