Insect-Inspired Strategy for Conferring Reversible, High Responsivity on Microgels to Dilute-Source CO 2 .

We described an insect-inspired strategy for conferring reversible, high responsivity on polymer microgels to dilute-source CO 2 (≤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 2 receptor subunits in mosquitoes for CO 2 response, laser light scattering and related studies indicated that the CO 2 -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 2 -response mechanism. While this pushes the lower response threshold of CO 2 concentration down to ca. 1000 ppm, this unique strategy can also satisfy the urge to achieve both effective CO 2 capture and facile CO 2 release, making it possible to couple the detection with the capture and utilization of indoor excess CO 2 .