Multifunctional silver-doped strontium hexaferrite nanoparticles: Magnetic, optical, photocatalytic, and antimicrobial properties

Abstract

The magnetic Strontium hexaferrite nanoparticles (SrFe₁₂O₁₉) decorated with Silver (Ag) catalyst were designed to degrade Rhodamine B and Congo Red dyes, as well as to explore their antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. These nanoparticles were synthesized using a microwave-assisted combustion method, resulting in a series of Ag-decorated SrFe₁₂O₁₉ Nanoparticles. Characterization through PXRD, UV–visible DRS, Raman spectroscopy, and FE-SEM/TEM confirmed the formation of M-type hexagonal SrFe₁₂O₁₉ with uniformly distributed Ag NPs. The addition of Ag influenced the magnetic and optical properties of the SrFe₁₂O₁₉, with a slight decrease in optical band gaps and a reduction in saturation magnetization from 84 to 71 emu/g as Ag content increased to 10 ​wt%. Although the Ag decoration did not enhance the photocatalytic activity of SrFe₁₂O₁₉ for dye degradation under visible light, the photocatalysts were magnetically separable and reusable without significant efficiency loss. Moreover, the heterojunction exhibited a disinfection capacity that was five times quicker than the individual catalysts, highlighting its potential for environmental and antibacterial applications.