Construction and application of antimicrobial ultrafiltration membranes based on electro-stimulated hollow mesoporous carbon spheres and carbon nanotubes

The issue of fouling in the membrane separation processes still remains a huge challenge, due to a series of water pollutions, particularly in biological contamination. In this study, the hollow mesoporous carbon spheres (HMCS) were obtained by the template method, to serve as a slow-release carrier loaded with the broad-spectrum fungicide povidone-iodine (PVP-I). The unique structural properties of the HMCS addressed the issues related to the instability of iodine formulations, rapid iodine loss, and susceptibility to pollutant coverage. Subsequently, a separation membrane was developed by mixing aminated carbon nanotubes (CNT-NH 2 ) and HMCS loaded with PVP-I on the polyether sulfone (PES) substrate. The surface resistance of the composite membrane was reduced from 4.46 MΩ/sq to 12.36 kΩ/sq. The resulting composite conductive membrane exhibited a pure water flux exceeding 300 L·m −2 ·h −1 ·bar −1 and a dye removal efficiency of over 98 %. Additionally, the composite membrane presented antimicrobial properties, with the release of the effective iodine from PVP-I triggered by the conductive network under the applied electric field (ca. 1.99 times more than the self-release). The integration of the antimicrobial slow-release materials facilitated by the electric field presents a promising strategy for mitigating membrane fouling and reducing antimicrobial loss in membrane technology.