Perspective on Polymer Membranes for Hydrogen and Carbon Dioxide Separation

The efficient separation of hydrogen (H 2 ) and carbon dioxide (CO 2 ) mixtures represents a critical step in clean H 2 production, where environmentally friendly and energy-saving membrane technology serves as a promising solution. The key to realizing practical applications of membrane separation technology lies in the rational design and development of polymeric membrane materials that simultaneously exhibit high permeability and high selectivity. However, polymeric membrane materials face challenges in efficiently separating H 2 and CO 2 with similar molecular sizes. This review systematically summarizes recent research progress in polymeric membrane materials for H 2 and CO 2 separation. It focuses on analyzing the characteristics and separation performance of various material systems, including poly(ethylene oxide) (PEO), polyimides (PIs), polybenzimidazoles (PBIs), carbon molecular sieve membranes (CMSMs), polyamides (PAs) and polyarylates (PARs), and covalent organic framework (COF) membrane. The review thoroughly discusses current key challenges and technical bottlenecks of polymer membranes for hydrogen and carbon dioxide separation, while also providing insights into future development directions.