Metal-coordinated sub-10 nm membranes for water purification.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31519877.
- Also identified by DOI 10.1038/s41467-019-12100-0 and PMC identifier 6744495.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
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<sup>3+</sup> and Zr<sup>4+</sup> can generate defect-free structure while MOPM-Fe<sup>3+</sup> with superhydrophilicity is preferred. The membrane thickness is minimized to 8 nm by varying the ligand concentration and the pore structure of MOPM-Fe<sup>3+</sup> is regulated by varying the Fe<sup>3+</sup> content. The membrane with optimized MOPM-Fe<sup>3+</sup> composition exhibits prominent water permeance (109.8 L m<sup>-2</sup> h<sup>-1</sup> bar<sup>-1</sup>) with dye rejections above 95% and superior stability. This strong-coordination assembly may enlighten the development of ultrathin high-performance membranes.