Green synthesis on nanostructured Ag/TiO ₂ alginate film for dye contaminants photodegradation

Abstract Gel materials usually exhibit special physical and chemical properties such as high swelling and porosity. They have been widely applied in many fields, including chemical engineering, biology, medicine, and new materials. Nanoscale TiO 2 materials have been proven to exhibit the properties of photocatalytic decomposition of organic substances and can be used for the removal of organic dye wastewater. In this paper, Sodium alginate-silver/titanium dioxide (SA-Ag/TiO 2 ) gel films with photocatalytic activity were prepared. The film stably immobilized nanoscale silver (Ag) and TiO 2 within the gel film, and sodium alginate served as both an embedding agent and a reducing agent. SEM characterization revealed that the SA-Ag/TiO 2 surface exhibited a spongy, loose, porous gel structure. UV–vis and EDS confirmed the presence of nano-Ag and TiO 2 . Contact Angle experiments confirmed that the film material was hydrophilic. The preparation method for SA-Ag/TiO 2 gel film has the advantages of environmental friendliness, high cost-performance, simple operation, and controllable parameters. Compared with traditional adsorption, photocatalysis can completely decompose methylene blue (MB) and sunset yellow (SY) dyes, and has broad application prospects.