Mechanochemical Synthesis of Type III Porous Liquids from Solid Precursors for the Removal and Conversion of Waste CO₂ from CH₄

Abstract Porous liquids (PLs) have emerged as a promising class of flow porous materials, offering distinctive benefits for sustainable separation processes coupled with catalytic transformations in the chemical industry. Despite their potential, challenges remain in the realms of synthesis complexity, stability, and the strategic engineering of separation and catalytic sites. In this study, a scalable mechanochemical synthetic approach is reported to fabricate Type III PLs from solid precursors with high stability. In these Type III PLs, ZIF‐8 nanocrystals are dispersed in the deep eutectic solvents formed by solid hydrogen‐bond donors and acceptors. Owing to the presence of multiple interfacial hydrogen and coordination bonds, these PLs not only maintain porosity and fluidity with high stability, enabling efficient CH₄ purification by CO₂ removal and sequestration, but also facilitate the catalytic conversion of stored CO₂ into valuable products under ambient conditions. This strategy advances the green production of stable and well‐dispersed PLs, showing the potential of PLs in the sustainable separation and catalysis coupling system in the chemical industry.