Superhydrophilic Sub-1-nm Porous Membrane with Electroneutral Surface for Nonselective Transport of Small Organic Molecules
Lu Tan1, Li Gong1, Siyan Wang1, Yuzhang Zhu2, Feng Zhang1*（张丰）, Yatao Zhang3, and Jian Jin1*（靳健）
1College of Chemistry, Chemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China
2 i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, P. R. China
3School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China
ACS Appl. Mater. Interfaces2020, 12, 38778--38787
The study of traditional Chinese medicines (TCMs) is receiving increasing attention worldwide because of their contribution to human health. Developing an effective and sustainable method for screening TCMs is highly desired to accelerate the modernization of TCMs. In this work, we report a neutrally charged membrane made of a positively charged polyelectrolyte electrostatically assembled on a negatively charged superhydrophilic nanoporous membrane. The composite membrane possesses stable electroneutrality in a wide pH range and can precisely and nonselectively separate various charged molecules in TCMs with a transmittance higher than 90% for molecules with molecular weight (Mw) < 400 and a high rejection of 90% for molecules with Mw > 800. In addition, the membrane exhibits a superior antifouling performance, and the recovery ratio observed during a continuous cycling test of a simulated TCM solution was more than 93%. The combination of superhydrophilicity and electroneutrality in a nanoporous membrane provides a new route for designing nanofiltration membranes for highly efficient molecule separation and is promising for screening TCMs.