Preparation of Silver Nanoparticles Using Sodium Dithionite as Reducing Agent

Nano-sized silver powder was prepared by dropwise adding sodium dithionite solution to the solution of silver ethylene diamine tetraacetic acid(EDTA) complex.The effects of silver nitrate concentration,dosage of complexing agent,concentration of reducing agent,pH,reaction temperature,stirring speed,and adding speed of reducing agent solution on silver particle size have been investigated.The crystal structure and morphology of silver particles prepared were characterized using X-ray diffraction(XRD) and field emission scanning electron microscope(FESEM).The experimental results showed that silver particles with an average size of 58 nm were prepared under the conditions such as Ag-EDTA complex solution concentration of 0.005 mol/L,excessive amount of EDTA of 10%,pH of 11.5,reductant concentration of 0.0075 mol/L,stirring speed of 400 r/min,reaction temperature of 50 ℃ and reductant adding speed of 0.06 mL/s.