A review on facilitated transport membranes based on π-complexation for carbon dioxide separation

The emission of CO2 from human activities is the principal reason for global warming. Membrane separation technology has been extensively regarded as a tremendous potential option for mitigating CO2 emissions when utilizing fossil fuels as a major source of energy. As an important group of CO2 separation membranes, the fixed CO2 carrier-facilitated transport membrane guided by π-complexation reactions is a rising research field and has attracted much attention in the last ten years due to its desirable CO2 separation performance in the dry state and high resistance to oxidation. In this review, facilitated transport theories derived from π-complexation reactions are discussed for an in-depth understanding, rational design and tunable fabrication of facilitated transport membranes. According to the different fixation methods of metal ions (CO2 active carrier), polymer electrolyte membranes and mixed matrix membranes are discussed in detail as two strategies for fabricating CO2-facilitated transport membranes. Future perspectives toward π-complexation reaction-facilitated transport membranes are proposed.