Sciencemadness Discussion Board

Test to confirm presence of silver nanoparticles?

Nhaines - 29-1-2014 at 09:40

I believe I may have discovered a route to silver nanoparticles..

What way can I test to verify that the yielded material is in fact SN?

AJKOER - 29-1-2014 at 14:54

In the dark add a little HCl to the suspected solution of silver nanoparticles. Then, add ammonia to dissolve the precipitate.

Expose the solution to bright light. There should be a obvious darkening of the solution.


"To quote "The Columbia Encyclopedia", 6th ed., 2011:

"Silver chloride
silver chloride chemical compound, AgCl, a white cubic crystalline solid. It is nearly insoluble in water but is soluble in a water solution of ammonia, potassium cyanide, or sodium thiosulfate ( "hypo" ). On exposure to light it becomes a deep grayish blue due to its decomposition into metallic silver and atomic chlorine. This light-sensitive behavior is the basis of photographic processes (see photography , still ). Since silver bromide, AgBr, and silver iodide, AgI, react similarly, all three of these silver halide salts are used in making photographic films and plates. Both the bromide and iodide are less soluble in water and more sensitive to light than the chloride. The bromide forms light yellow cubic crystals; the iodide forms yellow hexagonal or yellow-orange cubic crystals, depending on the temperature. Besides use in photography, silver chloride is used in silver plating, and silver iodide is used for seeding clouds. The chloride, bromide, and iodide occur naturally as the minerals cerargyrite, bromyrite, and iodyrite, respectively. Silver fluoride, AgF, forms colorless cubic crystals; it is much more soluble in water than the other silver halides."


[Edited on 29-1-2014 by AJKOER]

vmelkon - 30-1-2014 at 14:47

I think he meant that he tried to prepare silver nanoparticles and wants a test to determine their size. A chemical test is not going to work.
In nanoparticle synthesis it is very important to control not only the particle size but also the particle shape and morphology as well. In the present investigation the synthesis of silver nanoparticles by chemical route [4,5] is discussed, which is an easy, simple and convenient route for preparing metal particles in nanometer range. The prepared silver nano particles have been dispersed in chloroform and then examined using X-ray diffraction (XRD), Transmission Electron Microscope (TEM) and UV/Vis absorption spectroscopy. These studies reveal that the prepared nanoprticles are of an average size of 16 nm, which indicates the importance of the present work. "

and don't forget to look at the TEM photo. Those are 16 nm diameter spherical particles.