Preparation and properties of the silver loaded activated carbon fibers

Using viscose fiber as precursor, a novel silver loaded activated carbon fiber (Ag-ACF) was prepared by precursor silver-loaded method. Structure of Ag-ACFs was characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and its antibacterial property, durability, chemical stability and in vitro cytotoxicity were also studied. The results showed that silver particles on the Ag-ACF were distributed evenly at nanoscale size, the average size of the silver particles was about 20-40 nm and its existence format was Ag0. The prepared Ag-ACF had excellent antibacterial performance. When the silver content of the Ag-ACFs was about 2273 mg/kg, the bacterial inhibitive rate against Candida albicans (C.albicans), Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) exceeded 99.99 %. There was no obvious decrease on silver content and antibacterial activity of the Ag-ACF after exposure to 50 times consecutive ultrasonic washing conditions, which indicated that the Ag-ACF has excellent durability. The Ag-ACF has strong alkali resistance and weak acid resistance. However, the Ag-ACF treated with 0.2 mol/l HCl or CH3COOH aqueous solution can still maintain excellent antibacterial property. The level of in vitro cytotoxicity of the Ag-ACF was grade 1, implying no obvious cell cytotoxicity, which fully embodies its excellent biological safety performance.