Ultrafast and On-Demand Oil/Water Separation Membrane System Based on Conducting Polymer Nanotip Arrays
Zhengao Wang, Peng Yu, Jiajia Zhou, Jingwen Liao, Lei Zhou, Heying Ran, Jingxia Zhai, Jun Xing, Guoxin Tan, Zhengnan Zhou, Yangfan Li, Chengyun Ning, Yahong Zhou
Abstract
Ultrafast oil/water separation based on tunable superwettability switch remains a big challenge. Here, inspired by the ultrafast water transport mechanism in sarracenia, we develop a micro/nanostructured porous membrane with conducting polymer nanotip arrays through the surface-initiated polymerizations. By modulating the height (ranging from 49–529 nm) and redox states of nanotips, a smart reversible superwettability switch is facile to obtain with contact angles of water/oil arranging from 161° to about 0°. Besides, liquid transport speed was accelerated more than 1.5 times by increasing the nanotip length. The water flux could reach up to 50326 L m–2 h–1 (1000 times that of a typical industrial ultrafiltration membrane). This is attributed to the stable and continuous water film along the nanotips, which provide a lubrication layer, leading to an increase of permeability. This work provides significant insights into macro/nanostructured membrane design for smart separation, blood lipid filtration, and smart nanoreactors with high permeability.