The efficacy of water and wastewater treatment improves with the development of a reusable dual-faced membrane. The covalent organic framework (COF) membrane is synthesized in a matter of minutes by use of microwave technology and is also equipped with strong antibacterial properties to ensure durability and effectiveness.

The one-step microwave-mediated synthesis performed at the liquid-water vapor interface assures precision in infusing the membrane with specific properties. It can be tailored to capture different types of water pollutants and features superhydrophilic and near-hydrophobic surfaces for the efficient removal of oils, dyes and other types of contaminants. The superhydrophilic membrane surface enables fast water flux while increasing resistance to fouling and ensuring high rejection rates for various pollutants.

Laboratory tests evaluated the performance of self-standing COF membranes with thicknesses of 25 μm, 55 μm and 85 μm. As reported in the Journal of the American Chemical Society, the devices demonstrated exceptional performance in removing oil from oil-in-water mixtures and were characterized by a water flux of approximately 3,600 l/m²/h, a performance attributed to their multilayered structure and consistent porosity. Excellent rejection rates for anionic dyes with sizable molecules were also documented, along with significant antimicrobial efficacy against bacteria such as E. coli and S. aureus, while being biocompatible.

"Our method not only simplifies the production process but also enhances the separation capabilities of the membranes, offering a promising solution to critical water purification challenges worldwide," said the researchers.

Scientists from New York University Abu Dhabi, Technology Innovative Institute (Abu Dhabi), Normandie University (France) and Material Science Institute of Madrid (Spain) contributed to this development.