Preparation method of Ag nano particles

The invention provides a preparation method of Ag nano particles. The method is characterized in that a high-voltage direct-current power supply is used for providing electric energy, a platinum needle is taken as an anode, an AgNO3 solution is driven by a peristaltic pump to flow through a buffer bottle and overflows from the top end of a capillary tube where a graphite carbon rod penetrates, andthe overflowing solution is taken as a discharge cathode; when enough high voltage is applied between the two electrodes, the overflowing solution generates glow to form plasma, active particles generated by the solution cathode glow discharge plasma react with Ag+ in the solution, and generated Ag nano particle turbid liquid flows into a collector along the wall of the graphite carbon rod; and finally the turbid liquid is subjected to ultrasonic dispersion, centrifugal separation, washing by distilled water, drying to constant weight, and grinding to obtain the Ag nano particles. The Ag nanoparticles synthesized thr