Ultra-thin films colorimetric sensors with highly absorbent media

Abstract

Colorimetric sensing, which converts environmental changes into visible color changes, provides a simple yet powerful detection mechanism that is well-suited for the development of low-cost and low-power sensors. A new approach to colorimetric sensing uses the structural color of the photonic crystal to create color-changeable materials that are subject to environmental changes. Since a combination of introduced design methods for colorimetric detection, inspired by photonic structures, depends on highly ordered structures and periodically arranged refractive indices, concomitant co-assembling of multiple materials and micro/nano building blocks to achieve uniform colors at a large scale constrains their rapid and convenient fabrication. In this study, this thesis presents ultra-thin films colorimetric sensors with highly absorbent media. The ultra-thin films, as a simple structure, can be easily fabricated in various patterns with flexibility, even it is a powerful color-tunable structure. Recently, in our ongoing research, ultra-thin films exhibited colorimetric properties with sensitive color shifts in external refractive index change and subtle variations of coating thickness. With these properties, through the research process, optimal structures of ultra-thin films for each external environment changes will be designed and fabricated with flexible large-area samples.