Ja-Hyun Gu, a graduate student (Ph.D. candidate) in Professor Kwang-Woon Jeong's research team (Department of Polymer -Nano Science &Technology&Graduate School Department of Nano Convergence Engineering), has developed a smart fluorescent material that can be optically patterned and whose optical properties can be controlled by temperature and time.

The results of this research were selected as the cover article of the June 2022 issue of Advanced Optical Materials (IF=9.926), a prestigious international journal in the field of materials science.

The research team introduced cyclosiloxane into liquid-crystal molecules exhibiting aggregation-induced emission and photoisomerization characteristics to induce a unique monotropic phase behavior. They then closely investigated changes in transmittance and fluorescence in response to light, temperature, and time, identifying and elucidating the underlying mechanism.

Using the developed material, the team also demonstrated variable optical patterns and multi-responsive smart sensors, showing its potential as a smart optical material.

In particular, the material developed in this study is significant from a molecular-engineering perspective because it simultaneously exhibits intrinsic molecular properties and effects resulting from control of molecular packing structure.

In this study, Ja-Hyun Gu, a Ph.D. candidate in Professor Kwang-Woon Jeong's research team, served as first author and led the overall research. As first author, Gu has published five SCI papers to date and has received two outstanding paper presentation awards at domestic and international conferences, attracting attention as a next-generation researcher. In 2019, Ja-Hyun Gu was selected for the National Research Foundation of Korea's Program for Supporting the Next Generation of Scholars [Doctoral Student Research Incentive], which enabled independent research.

Researcher Ja-Hyun Gu said, "This study showcases the subtlety of molecular engineering," and added, "I hope this work will be regarded as offering new insights across optics and related fields."

Meanwhile, this research was carried out with support from the National Research Foundation of Korea's Basic Research Laboratory Support Program and Mid-Career Researcher Support Program.