Ag@Fe₂O₃‑GO Nanocomposites Prepared by a Phase Transfer Method with Long-Term Antibacterial Property

Silver has been utilized as a highly effective and broad-spectrum antibacterial agent in our daily life. However, low stability, poor long-term antibacterial efficiency, and potential environmental hazard of released Ag⁺ ions may limit its practical applications. Ag-graphene oxide (GO) nanocomposites have been reported to display highly enhanced antibacterial property, yet their stability and long-term antibacterial properties have not been carefully investigated. Herein, we report the synthesis of Ag@Fe₂O₃-GO nanocomposites with tunable loading density up to full monolayer coverage by adopting a simple phase transfer method. Compared to Ag@Fe₂O₃, its GO composite shows enhanced stability with Ag⁺ releasing rate decreased by more than two times under dialysis condition. We discover that the presence of GO not only slows down Ag nanoparticle oxidation process but also enables Ag⁺ ions recrystallization on GO surface. The Ag@Fe₂O₃-GO nanocomposites have shown better and long-term antibacterial property against both Gram-negative and Gram-positive bacteria than those of plain Ag and Ag@Fe₂O₃, displaying great potential as a promising long-term bactericide with suppressed environmental hazard.