Light-Triggered CO₂ Breathing Foam via Nonsurfactant High Internal Phase Emulsion

Solid materials for CO₂ capture and storage have attracted enormous attention for gaseous separation, environmental protection, and climate governance. However, their preparation and recovery meet the problems of high energy and financial cost. Herein, a controllable CO₂ capture and storage process is accomplished in an emulsion-templated polymer foam, in which CO₂ is breathed-in under dark and breathed-out under light illumination. Such a process is likely to become a relay of natural CO₂ capture by plants that on the contrary breathe out CO₂ at night. Recyclable CO₂ capture at room temperature and release under light irradiation guarantee its convenient and cost-effective regeneration in industry. Furthermore, CO₂ mixed with CH₄ is successfully separated through this reversible breathing in and out system, which offers great promise for CO₂ enrichment and practical methane purification.