Metal-coordinated sub-10 nm membranes for water purification

• Published in: Nature communications Vol. 10; no. 1; pp. 4160 - 10
• Main Authors: You, Xinda, Wu, Hong, Zhang, Runnan, Su, Yanlei, Cao, Li, Yu, Qianqian, Yuan, Jinqiu, Xiao, Ke, He, Mingrui, Jiang, Zhongyi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 13.09.2019; Nature Publishing Group; Nature Portfolio
• Subjects: 631/57/2271; 639/638/911; 704/172; Aqueous solutions; Fabrication; Ferric ions; Humanities and Social Sciences; Hydrophilicity; Ionization; Ionization potentials; Iron; Membrane permeability; Membranes; Metal ions; multidisciplinary; Organophosphates; Phytic acid; Porosity; Purification; Science; Science (multidisciplinary); Thickness; Water purification
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-12100-0

Ultrathin membranes with potentially high permeability are urgently demanded in water purification. However, their facile, controllable fabrication remains a grand challenge. Herein, we demonstrate a metal-coordinated approach towards defect-free and robust membranes with sub-10 nm thickness. Phytic acid, a natural strong electron donor, is assembled with metal ion-based electron acceptors to fabricate metal-organophosphate membranes (MOPMs) in aqueous solution. Metal ions with higher binding energy or ionization potential such as Fe 3+ and Zr 4+ can generate defect-free structure while MOPM-Fe 3+ with superhydrophilicity is preferred. The membrane thickness is minimized to 8 nm by varying the ligand concentration and the pore structure of MOPM-Fe 3+ is regulated by varying the Fe 3+ content. The membrane with optimized MOPM-Fe 3+ composition exhibits prominent water permeance (109.8 L m −2  h −1  bar −1 ) with dye rejections above 95% and superior stability. This strong-coordination assembly may enlighten the development of ultrathin high-performance membranes. Ultrathin membranes have demonstrated great promise for water purification technologies owing to their high permeance. Here the authors fabricate sub-10 nm, defect-free, robust membranes for dye remediation from water through the coordination-driven assembly of metal-organophosphates.