A new strategy to accelerate co-deposition of plant polyphenol and amine for fabrication of antibacterial nanofiltration membranes by in-situ grown Ag nanoparticles

Abstract

Due to the far cheaper price than polydopamine, plant polyphenol and amine have been widely used for mussel-inspired chemistry. However, co-deposition of them still suffers the problem of long co-deposition time owning to the slow dissolution and diffusion of oxygen in solution. Herein, we reported an interesting strategy regarding addition of AgNO3 as both oxidant and Ag precursor into co-deposition of tannic acid and diethylenetriamine for nanofiltration (NF) membrane preparation. It was found that, AgNO3 addition not only shortened co-deposition time, but also in-situ generated Ag nanoparticles and rendered membrane surface antibacterial activity. The effect of AgNO3 addition on co-deposition behavior, physicochemical properties, separation and antibacterial performance of the as-prepared NF membrane were systematically investigated. The results showed that, when 0.15 wt% AgNO3 was added, the prepared NF membrane possessed a pure water flux of 5.36 L m−2h−1 bar−1, a MgCl2 rejection of 86.5% and an excellent antibacterial activity. This study not only provided a facile and effective strategy to prepare antibacterial NF membrane, but also offered new insights into co-deposition of polyphenol and amine for more widespread applications.