CuSo4 + Ascorbic Acid

Daedronus, Tue Jul 02 2013, 10:36PM

This seems to be a rather obscure method to obtain copper nano particle (to be used for example in a conductive paint).
What I'm looking for is more information about the reaction, the ideal proportion and concentration of the solutions or just more information in general.

Thanks
Re: CuSo4 + Ascorbic Acid
Scott Fusare, Fri Jul 05 2013, 12:56PM

I fooled with this a bit last summer. As I recall there are several papers addressing it that were not behind pay walls.

I always began with a saturated solution of either straight up CuSO4 or CuSO4 complexed with ammonium hydroxide. From there the amount of ascorbic acid added was somewhat random, this was a demo for my daughter and very much "off the cuff" in nature.

The solutions containing ammonium hydroxide tended to yield the "nano-particle" suspensions with little to no precipitate. One of the papers attempted to compare the color of the resultant solution with the particle size produced. Occasionally I would get the "copper mirror" effect with sections of the glassware plating in a nice shiny and tenacious copper film. Picture and a bit of detail here Link2

Solutions of straight CuSO4 tended to yield much larger copper particles that would settle to the bottom. This ranged from a wonderfully fine powder to an agglomerated, gummy mass depending on conditions.