Molecular Dynamics Simulations of Interfacial Microstructure and Molecular Controlled CO₂ Transport in DES-Supported...

Understanding how interfacial microstructure governs gas transport in supported liquid membranes is essential for rational membrane design. Here, molecular dynamics simulations are used to interrogate PVDF-supported DES membranes doped with MoS₂, MXene, ZIF-8, and SiO₂, with the solid-liquid interface being the primary criterion for separation. This study finds that DES-particle interactions dominate energies, while direct CO₂-particle interactions are weak. The influence of doped particles manifests itself in the form of morphological changes in the DES, which in turn alter the structural environment within the membrane. Among the four fillers, the MXene-doped membrane exhibits the highest CO₂ permeation under identical conditions. Further size-regulation analysis within the MXene system indicates that excessive fragmentation into very small domains can induce aggregation/stacking, which partially blocks local dissolution-diffusion pathways and thereby reduces the net separation efficiency. These results identify composition-orientation coupling and kinetic trapping as the primary controls of transport. This study reveals that solvent particles affect gas separation at the molecular level, which may enhance the creation and design of two-dimensional materials in the future.