서강대학교

초록/요약

Tunable photonic crystals (TPCs) represent an important class of intelligent materials, which can be used as optically active components and as functional technology to change an object’s color. Colorimetric sensing based on TPCs, which transduces environmental changes into visible color changes, provides a simple and powerful detection mechanism that is well-suited to the development of low-cost and low-power sensors. In another application, electrically responsive PCs represent one of the most promising tunable photonic band gap (PBG) materials for technological applications such as display technologies, artificial camouflage, etc. The thesis aims not only to improve the performance of chemically and electrically TPC but also to present a novel fabrication method and a new class of TPC. The first objective is to propose a fast responsive the photonic crystal-polymer composite based chemical sensor. To achieve fast response time, the nanoscale easy tear (NET) process inspired by easy tear package is presented and its physical mechanism is verified through multiphysics numerical simulation. Patterning photonic crystal-polymer composite was performed through the NET process combined with wettability contrast or inkjet printing and ultra-fast responsive VOCs sensor and humidity sensor is demonstrated based on the proposed method. The second objective is to propose a new class of electrically TPC, that is, a flexible all-solid-state electrically TPC. Until now, many types of electrically TPC have been presented but they can work in the specific liquid cell. Owing to cooperation of chemically induced swelling to photonic crystals-PDMS composite and stretching control by DEAs, for the first time, the flexible all-solid-state electrically TPC was realized and its novel characteristics (wide, repeatable, and reliable color change, and working on curved surfaces) and the fabrication methods for achieving them were studied.