Polyamide nanofiltration membrane with highly uniform sub-nanometre pores for sub-1 Å precision separation

• Published in: Nature communications Vol. 11; no. 1; pp. 2015 - 9
• Main Authors: Liang, Yuanzhe, Zhu, Yuzhang, Liu, Cheng, Lee, Kueir-Rarn, Hung, Wei-Song, Wang, Zhenyi, Li, Youyong, Elimelech, Menachem, Jin, Jian, Lin, Shihong
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 24.04.2020; Nature Publishing Group; Nature Portfolio
• Subjects: 140/146; 147/135; 147/143; 147/3; 639/166/898; 639/301/923/1028; 639/925/357/551; Diffusion rate; Fabrication; Humanities and Social Sciences; Ions; Membranes; Monomers; multidisciplinary; Nanofiltration; Nanotechnology; Polyamide resins; Polyamides; Polymerization; Pore size; Pores; Porosity; Rejection; Science; Science (multidisciplinary); Self-assembly; Separation; Solutes; Surfactants
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-15771-2

Separating molecules or ions with sub-Angstrom scale precision is important but technically challenging. Achieving such a precise separation using membranes requires Angstrom scale pores with a high level of pore size uniformity. Herein, we demonstrate that precise solute-solute separation can be achieved using polyamide membranes formed via surfactant-assembly regulated interfacial polymerization (SARIP). The dynamic, self-assembled network of surfactants facilitates faster and more homogeneous diffusion of amine monomers across the water/hexane interface during interfacial polymerization, thereby forming a polyamide active layer with more uniform sub-nanometre pores compared to those formed via conventional interfacial polymerization. The polyamide membrane formed by SARIP exhibits highly size-dependent sieving of solutes, yielding a step-wise transition from low rejection to near-perfect rejection over a solute size range smaller than half Angstrom. SARIP represents an approach for the scalable fabrication of ultra-selective membranes with uniform nanopores for precise separation of ions and small solutes. Separating molecules or ions with sub-Angstrom scale precision is important but technically challenging. Here, the authors demonstrate that precise solute-solute separation can be achieved using polyamide membranes formed via surfactant-assembly regulated interfacial polymerization.