Naslov
Preparation of Highly Concentrated Stable Dispersions of Uniform Silver Nanoparticles

Autori
Sondi, Ivan ; Goia, V.Dan ; Matijević, Egon

Izvornik
Journal of Colloid and Interface Science (0021-9797) 260 (2003); 75-81

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
nanoparticles; silver; precipitation

Sažetak
Stable aqueous dispersions of concentrated silver nanoparticles of narrow size distribution were prepared by reducing silver nitrate solutions with ascorbic acid in the presence of Daxad 19 (sodium salt of a high molecular weight naphthalene sulfonate formaldehyde condensate) as stabilizing agent. The latter has excellent ability to prevent the aggregation of nanosize silver at high ionic strength and high concentration of particles (up to 0.3 mol dm-3). The presence of the dispersing agent on the surface of silver particles was confirmed by ATR-FTIR spectroscopy and electrokinetic measurements, explaining both the negative charge over the entire pH range, and the electro-steric effect responsible for their long-term stability. The other experimental conditions, i.e., the pH of the reacting solutions, the concentration of the stabilizing agent, and the metal/dispersant ratio, also have a significant impact upon the size and the stability of these dispersions. The final nanosize silver can be obtained as dried powder, and fully redispersed by sonication in deionized water.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA