Photonic CuxO Structures as Colorimetric CO/CO2 Sensors

• Applicants: Professorin Kaline Pagnan Furlan, Ph.D.; Dr. Diego Ribas Gomes
• Subject Area: Glass, Ceramics and Derived Composites ; Coating and Surface Technology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 542925291

This project aims at developing self-sustaining, label-free, colorimetric sensors for carbon monoxide (CO) and carbon dioxide (CO2) detection, utilizing the concept of adaptable 3D photonic structures composed of copper oxides (CuxO). These 3D structures exhibit refractive index modulation, either with long- or short-range periodicity, resulting in photonic bandstops or reflection edges that manifest as structural colors within the visible wavelength spectrum. The hypothesis revolves around leveraging the phase changes induced in CuxO by the interaction with CO/CO2, leading to observable shifts in structural color, enabling a straightforward, naked-eye assessment of gas exposure without the need for external power or underlying electronics. Building on our expertise in manipulating the reflective properties of photonic structures, the goal is to create CuxO photonic structures with short-range order, referred to as photonic glasses (PhGs). These PhGs will feature tunable structural color due to reaction-induced refractive index changes. The project will investigate the interplay between the 3D photonic structure's parameters, such as macropore size, volume filling, and oxide phase ratios, influencing their colorimetric response pre and post-exposure to CO/CO2. The focus is on in-situ characterization methods, tracking the morphology changes and alterations in optical properties induced by gas exposure and gas-solid reactions. The ultimate aim is to provide a user-friendly, photonic-based label-free colorimetric sensor for facile gas exposure assessment.

• DFG Programme: Research Grants