Spray coating vapor-phase interfacial polymerization: A new approach for developing 2D nanosheet enabled thin film nanocomposite membranes to remove heavy metal ions

Alternate to the conventional dip coating method, a new eco-friendly approach has been used to develop thin-film nanocomposite (TFN) membranes in this research work, all while preserving the exceptional separation capabilities of TFN membranes. The methodology is altered by employing spray coating and implementing vapor-phase interfacial polymerization (VP-IP) to craft thin-film nanocomposite membranes. This innovative approach significantly reduces reagent consumption and eliminates the need for organic solvent (n-hexane). By incorporating amine-functionalized graphene oxide (GO-NH-NH2) as a nanofiller, we have fabricated both thin-film nanocomposite (TFN) and thin-film composite (TFC, without nanofiller) membranes. Developed membranes were characterized with various physicochemical characterization techniques and tested against heavy metal ions. The membranes demonstrated outstanding performance, with ∼ 96 % rejection of Na2SO4, ∼95 % rejection of Pb(NO3)2, ∼94 % rejection of CuSO4, and ∼ 92 % rejection of CdSO4 salt with highest pure water flux 46.57 Lm2h−1. The antifouling characteristics and antibacterial activity of the membrane were also assessed, revealing that including nanosheets has substantially elevated the antifouling properties, notably by increasing the flux recovery ratio. Furthermore, the prepared membranes exhibited enhanced antibacterial performance after incorporating these nanosheets.