Gas separation membranes are essential for the capture, storage, and utilization (CSU) of CO₂, especially for H₂/CO₂separation. However, both glassy and rubbery polymer membranes lead a relatively poor selectivity for H₂/CO₂ separation because the differences in kinetic diameters of these gases are small. The present study establishing the mixed matrix membranes (MMMs) consist of a nano-sized zeolitic imidazolate frameworks (ZIF-8) blended with the polysulfone (PSf) asymmetric membranes. The gas transport properties (H₂, CO₂, N₂, and CH₄) of MMMs with a ZIF-8 loading up to 10 wt% were tested and showing significant improvement on permeance of the light gases (e.g., H₂ and CO₂). Moreover, the depositional polydopamine (PDA) layer further enhanced the ideal H₂/CO₂ selectivity, and the PDA-modified MMMs approach the Robeson upper bound of H₂/CO₂ separation membranes. Hence, the PDA post-modification strategy can effectively repair the defects of MMMs and improved the H₂/CO₂selectivity.

气体分离膜对于CO ₂的捕获，储存和利用（CSU）至关重要，尤其是对于H ₂ / CO ₂分离。然而，玻璃状和橡胶状聚合物膜都导致相对较差的H ₂ / CO ₂分离选择性，因为这些气体的动力学直径差异很小。本研究建立了混合基质膜（MMM），由纳米级沸石咪唑酸酯骨架（ZIF-8）与聚砜（PSf）不对称膜混合而成。气体传输特性（H ₂，CO ₂，N ₂和CH ₄测试了具有高达10 wt％的ZIF-8负载的MMM，它们显示出轻质气体（例如H ₂和CO ₂）的渗透性显着改善。此外，沉积聚多巴胺（PDA）层进一步提高了理想的H ₂ / CO ₂选择性，并且PDA修饰的MMM接近H ₂ / CO ₂分离膜的Robeson上限。因此，PDA后修饰策略可以有效地修复MMM的缺陷并提高H ₂ / CO _2的选择性。