Acid-resistant and thermally stable PEEK-PANI@MIL-101 membranes via dual in-situ growth strategy for high-efficiency dye separation from organic solvents

Polymer-MOF composite membranes have attracted the attention of researchers in the field of organic solvent nanofiltration by fully utilizing the synergistic advantages of the processability of polymers and the molecular sieving properties of metal-organic frameworks (MOFs). However, the performance of such composite membranes in organic solvents is greatly reduced by insufficient interfacial interactions at the polymer-MOF interface. In this study, an in situ co -construction strategy of polyaniline (PANI) and MOF was employed to create a stabilized interface on the polymer matrix while converting the poly(ether ether ketone) precursor substrate (PEEKt) into solvent-resistant PEEK to fabricate high-performance nanofiltration membranes for organic solvents (PEEK-PANI@MIL-101). This composite membrane exhibits a rejection rate exceeding 97 % for Rose Bengal (RB) in ethanol solution, coupled with an ultrahigh ethanol permeance of 266 L m −2  h −1  bar −1 . The integrated dual in situ growth strategy significantly enhances the interfacial adhesion of the composite membrane. Furthermore, the membrane demonstrates outstanding thermal resistance and acid stability, ensuring robust performance under harsh operating conditions.