[Preparation and characterization of activated carbon-silver composite with antibacterial behavior via NaBH4...

Activated carbon-silver composite (Ag/AC) for antibacterial behavior with capability of controlling silver release was prepared by NaBH4 reduction method. The antibacterial activity towards E. coil and resistance of water erosion was investigated through a point of view of water purification. N2 adsorption isotherm, Scanning electron spectroscopy (SEM)-Energy dispersive X-ray spectrometer(EDS) and X-ray diffraction(XRD) was used to characterize the surface morphology and pore properties. As an experiment result, silver was deposited on AC in the state of Ag0. The content of silver supported, specific surface area, nucleus formation and growth mechanism, particle size and distribution of the generated silver particles were determined by the concentration of the aqueous solution of AgNO3. With the increasing of AgNO3 solution concentration, the activity of the obtained Ag/AC changed from non-active to inhibitory and then to high antibacterial. Ag/AC supported silver content of 2.70% killed all the concentration of 2 x 10(6) CFU/mL of E. coil. However, it showed high resistance to water erosion that silver loss was 21.1% in 600 h for surging. High antibacterial activity and control silver release can be simultaneously realized by the NaBH4 reduction method.