Controllable deposition of Ag nanoparticles on various substrates via interfacial polyphenol reduction strategy for antibacterial application

The deposition of silver nanoparticles (Ag NPs) on different substrates is promising in antibacterial applications. But it is limited by the aggregation problem and complex deposition procedure of Ag NPs. Herein, facile fabrication of antibacterial substrates with controllable deposition of Ag NPs via polyphenol reduction strategy is presented. Polyphenol with surface independent coating property is used to in situ deposit Ag NPs on diverse substrates (e.g., cotton textile, copper foil, steel sheet, iron sheet, glass slide, rubber and plastic sheet) via the reduction of Ag⁺. The modified substrate shows several unique properties, including high color maintenance (4.7 % change from the original), sustained and pH-responsive Ag⁺ release behavior (about 40–10 % of Ag⁺ ions at pH values of 4–8 at day 9, respectively), large diameters of inhibition zones (over 1 cm) and low minimum inhibitory concentrations (0.1 mg mL^–1). The continuous contamination tests (5 cycles with the almost same effectiveness) and long-term stability analysis (over 25 days) manifest excellent recycling performance and stable antibacterial benefits. Finally, the results of practical applications on mask, shoe-pad and fresh box materials show that all the modified materials inhibited E. coli and S. aureus by more than 95 %. This work provides a versatile interfacial polyphenol reduction strategy for depositing Ag nanoparticles on various substrates. Such Ag-deposited product could be used for packaging and clothing sanitation.