ABOVE 44 silver atom cluster, consisting of a 32-atom Ag core (red and green) protected by six mounts, each containing two Ag atoms (blue) and five sulphur derivatives of benzoic acid (yellow is sulphur, grey is carbon, orange is oxygen). Credit: Bokwon Yoon
Dish containing 140 grams of silver nanoparticle powder pictured with a solution of the nanoparticles and 4 dice, which represent the shapes found within the highly symmetric cluster ‒ 4 of the five Platonic solids: icosahedron, dodecahedron, octahedron, and cube. Credit: Daniel Miller
NON-OXIDIZING SILVER NANOPARTICLES
Created by separate teams with similar methods
(Phys.org) —Two teams working independently of each other have developed very similar methods for creating silver nanoparticles that appear impervious to rust. One of the teams was from the U.S. and published their results in the journal Nature. The other team was from China and published their results in the journal Nature Communications.
Both teams were looking for a way to create silver nanoparticles that could be used as a replacement for the more expensive gold nanoparticles (used extensively in biomedical applications). Silver is more abundant and costs less but its sensitivity to oxidation makes it unstable, and thus unsuitable for most of the applications that gold nanoparticles are used for. To use silver as a basis for such nanoparticles the research teams had to find a way to cause them to be impervious to oxidation, and that’s just what both have achieved.
Both teams wound up with nanoparticles that were made up of exactly 44 silver atoms. Likewise both teams used a similar technique to create the nanoparticles—mixing silver nitrates with reagents in ethanol and water.
(2013 September 5 via phys.org news)
Ultrastable silver nanoparticles, Nature (2013) DOI: 10.1038/nature12523
All-thiol-stabilized Ag44 and Au12Ag32 nanoparticles with single-crystal structures, Nature Communications, DOI: 10.1038/ncomms3422