Application of silicone nanofilaments coatings towards point-of-use drinking water treatment: Assessment on trace Lead ions, dyes and oils removal

Abstract

A new coating-based approach for water treatment was demonstrated using silicone nanofilaments (SNF) coatings. In view of some existing point-of-use (POU)/point-of-entry (POE) water treatment systems, where membranes or filters are used to build devices that allow individuals to treat water on their own at the point of consumption. The reported coating-based approach offers an advantage as contaminated water was treated upon contact with the functionalized SNF-coated surfaces, without additional pressure or energy requirement. Besides, the coatings took the shapes of the substrates and demonstrated some different formats can be potentially deployed for POU devices. To illustrate the suggested approach, glass substrates of three different shapes (flat microscopic slides, walls of vials, and three-dimensional (3D) filter frits) were employed. Substrates were readily coated with SNF under ambient conditions via gas phase deposition based on the previous developed protocol, subsequently modified with (3-Mercaptopropyl)triethoxysilane (MPTES), and were used to treat 200 ppb of trace lead ions in water. Results suggested that the coatings as a facile mean to render surfaces/containers functional towards trace lead removal, and enhanced performance compared to their non-coated counterparts.In addition, the oil sorption capacities of the coated frits were also evaluated. By rendering the as-prepared frits amphiphilic, they were used to treat trace lead, water-soluble methylene blue, and oil-soluble Oil Red O dyes. Overall, the study demonstrated and evaluated the use of the SNF coatings by treating some model contaminants in different formats than the existing approaches. The ease of preparation and the flexibility of the approach presented provide opportunities for the design of new water treatment systems and more accessible POU/POE devices.