Fabrication of hierarchical structured Fe3O4 and Ag nanoparticles dual-coated silk fibers through electrostatic self-assembly

•Dual-coated silk fibers were prepared via hierarchical self-assembly.•High density of AgNPs/Fe3O4NPs were hierarchically coated on the fiber surface.•As-prepared functional silk fibers showed excellent magnetic property.

In the present work, special hierarchical structured Fe3O4 nanoparticles (Fe3O4NPs)/Ag nanoparticles (AgNPs) dual-coated silk fibers have been prepared via a simple electrostatic self-assembly technology. Silk fibers were sequentially immersed in solutions of positively charged AgNPs and negatively charged Fe3O4NPs. As-prepared hierarchical structured silk fibers were characterized by XRD, FESEM, and VSM. XRD and SEM characterizations demonstrated that silk fibers were hierarchically and uniformly coated by high dense AgNPs and Fe3O4NPs. VSM analysis indicated that the as-prepared ternary composite fibers showed excellent magnetic property.