Rational design of the PEBA2533 mixed matrix membrane containing metallo-supramolecular polymers for efficient CO2/H2 separation

Mixed-matrix membranes (MMMs) are an effective method for overcoming the trade-off limitations of conventional polymeric membranes and are attractive for CO2/H2 separation. However, major challenges remain in achieving high gas separation performance and long-term stability owing to undesirable polymer/filler interfaces. In this study, a novel metallo-supramolecular polymer (F127-Tpy-M) was designed and selected to engineer a polymer/filler interface. Benefiting from strong intermolecular interactions, F127-Tpy-M dispersed well in the PEBA2533 matrix with a defect-free interface. By synergistically combining the dipole-quadrupole effect of the ethylene oxide groups in F127 and gas-metal interactions, MMMs could significantly improve the gas separation performance. In comparison with the pristine membrane, the MMM with 60% F127-Tpy-M loading exhibited 175-194% and 215-259% increases in CO2/H2 selectivity and CO2 permeability, respectively, which far surpass the 2008 Robeson upper bound. The molecular dynamics simulations supported the experimental data, confirming that F127-Tpy-M is a promising candidate for designing next-generation highperformance MMMs.