ORGS1-0605
Spatially Programmed Water Condensation for Dynamic Retroreflective Color Graphics
Topic
GS1. Graduate Student Oral Session I: Colloidal and Interfacial Polymer Science
When and Where
Sep 28, 2026
16:00 - 16:12
Room 101
Session Chairs
Yoon-Ho HWANG
Jang-Hwan KIM
Hyosung AN
Presenter(s)
Hyejin Roh (KAIST)
Co-Author(s)
Abstract
Condensation typically gives rise to uncontrolled optical scattering and coloration; however, its transient liquid interfaces offer a potential platform for rewritable visual information when nucleation and growth are spatially regulated. Here, we demonstrate that lithographically engineered wettability patterns convert water condensation into a dynamic optical medium. Hydrophilic circular domains embedded within a hydrophobic matrix localize vapor condensation into synchronized arrays of liquid microinterfaces. As the droplets evolve, their curved air–water interfaces produce structural colors through multiple total internal reflections and optical interference. Contact-line pinning and depinning induce discrete optical transitions, whereas the size and spacing of condensation sites govern color hue, intensity, and temporal evolution. Leveraging these design principles, we realize multicolor patterns, temporally encoded hidden images, and breath-activated write–erase–rewrite cycles. These findings establish programmable condensation as a strategy for transforming a transient environmental phenomenon into a platform for dynamic optical information encoding.
