The study of nanosilver colloid with/without ammonia prepare by Submerged Arc Discharge Method

This paper uses Electrical Discharge Machining (EDM), Submerged Arc Discharge Method (SADM), and arc concentrated energy to ionize the medium of DI water. During submerged arc discharge, the silver metal surface melts and is condensed into a metal fluid containing Nano and Sub-micron particles by DI water after high temperature vaporization. There is no chemical byproduct produced in the process, and it is characterized by a simple and rapid process and green preparation. The procedure of this study runs as follows: (1) 200ml DI water is prepared as dielectric fluid; during submerged arc discharge, the electrode silver bar is molten in this dielectric fluid to prepare the Nano-Ag colloid; (2) 150ml DI water containing 5ml Nh3 is used as a dielectric fluid; the electrode silver bar is molten by a submerged arc discharge in this dielectric fluid to prepare the Nano-Ag colloid (Nh3-Ag) to be different from the former one. The two kinds of Nano-Ag colloid are analyzed by a UV-Vis spectrum analyzer and Zetasizer so as to work out the relationship between the surface plasmon resonance generated wavelength and absorbance. The Nano-Ag colloid derived from Nh3-Ag is compared with the Nano-Ag colloid derived from Ag. The Nh3-Ag particles have good stability, and the concentration and Zeta potential are increased.