Low-permeation resistance thin-film composite nanofiltration membrane based on high-precision 3D-printed support layer

Nanofiltration (NF) membrane technology, distinguished for high separation performance and energy efficiency, has been extensively employed in desalination and wastewater treatment. Herein, high-precision 3D printing is used to fabricate robust support layers featuring ideal straight-through micropores, effectively minimizing permeation resistance. To ensure the generation of a high-quality PA selective layer, electrospinning deposits a thin nanofiber layer that divides the support layer surface into fine grids. Finally, interfacial polymerization (IP) forms a PA selective layer on the membrane substrate, which is integrated by 3D-printed support layer and nanofiber layer, yielding a highly permeable composite NF membrane. With reduced permeation resistance and enhanced mechanical strength, the novel 3D-printed composite NF membrane maintains a long-term water permeance of above 22.5 L m −2  h −1  bar −1 , about double that of commercial NF270 membranes. Meanwhile, it achieves exceptional Na 2 SO 4 rejection of 97.8 % and superior anti-fouling performance. This study offers a promising approach to fabricating high-performance NF membranes using high-precision 3D printing, providing an innovative and scalable strategy for developing next-generation functional membranes.