Insect-Inspired Strategy for Conferring Reversible, High Responsivity on Microgels to Dilute-Source CO.

We described an insect-inspired strategy for conferring reversible, high responsivity on polymer microgels to dilute-source CO (≤5000 ppm in gas mixtures). This is demonstrated on oligo(ethylene oxide)-based microgels that contain tertiary amines on the polymer chains with proper organic small molecular carbonates in the polymer-solvent system. Similar to the synergistic contribution of the CO receptor subunits in mosquitoes for CO response, laser light scattering and related studies indicated that the CO-response of the microgels in terms of the volume changes works through the coordination of different functional moieties in the system, making it different from the conventional CO-response mechanism. While this pushes the lower response threshold of CO concentration down to ca. 1000 ppm, this unique strategy can also satisfy the urge to achieve both effective CO capture and facile CO release, making it possible to couple the detection with the capture and utilization of indoor excess CO.