Title:Production of Silver Nanoparticles Using High Voltage Arc Discharge Method
VOLUME: 12 ISSUE: 6
Author(s):Marek J. Kasprowicz, Anna Gorczyca and Piotr Janas
Affiliation:University of Agriculture in Krakow, Mickiewicza 21, Kraków, Poland.
Keywords:Arc discharge, ionic silver, silver colloids, silver electrodes, silver nanoparticles, tri-Sodium citrate.
Abstract:Background: Silver is the most often studied and the most used substance in the form of
nanoparticles. Currently, the production of silver nanoparticles (SNPs) reached the level of 320 tons
per year. SNPs consisting of approximately 20–15000 silver atoms. SNPs are most commonly used
as antimicrobial and antifungal agents in production of clothing, cosmetics, toys, paints, and in water
filters. In the field of medicine, SNPs are used in dentistry, orthopedics, surgery, and in the production
of medicines.
Methods: During electric discharge between silver electrodes, plasma is produced under the effect of
strong electric field with high temperature causing the removal of silver atoms from surface of the
electrodes. In aqueous solutions, dissociation of water into oxygen and hydrogen atoms occurs. The
interaction of active silver atoms with oxygen and hydrogen atoms and water particles causes the
formation of stable nanoparticle colloid.
Results: The arc discharge produces metallic silver nanoparticles and silver ions in water, tri-Sodium
citrate dehydrate (TSC), and ethanol. The size distribution of obtained SNPs has maximum size between
7 and 20 nm. The properties of colloidal silver prepared with HVAD method are analyzed by
UV-Vis spectroscopy, dynamic light scattering, and transmission electron microscopy. The stability
of silver colloids is tested thermal treatment under high pressure. On the basis of AAS measurements
of centrifuged colloids, silver ion to SNP ratio was estimated.
Conclusions: Using HVAD method, one can produce SNPs quickly with silver concentration of
approximately 15 ppm in various dispersant such as water, TSC solution, and ethanol. The aqueous
solution contains 4.5% silver ions and the 3.3 μM TSC solution contains 0.5% silver ions.