Synthesis of palladium nanoparticles

Patent metadata

Field	Value
Publication number	US-9932685-B2
Application number	US-201314375157-A
Country	US
Kind code	B2
Filing date	Feb 8, 2013
Priority date	Feb 9, 2012
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

A method of synthesizing metal nanoparticles is provided. The method includes submerging an electrically conductive substrate in a polysaccharide solution containing a predetermined concentration of a metal salt; applying an electric potential between the electrically conductive substrate and the polysaccharide solution for a predetermined period of time to form a polysaccharide layer containing metal nanoparticles on the electrically conductive substrate; re-dissolving the polysaccharide layer in a solvent to form a solution including the polysaccharide and the metal nanoparticles; and separating the metal nanoparticles from the polysaccharide.

First claim

What is claimed is:

1. A method of synthesizing metal nanoparticles, the method comprising:
submerging an electrically conductive substrate in a polysaccharide solution containing a predetermined concentration of a metal salt;
applying an electric potential between the electrically conductive substrate and the polysaccharide solution for a predetermined period of time to form a polysaccharide layer containing metal nanoparticles on the electrically conductive substrate;
dissolving the polysaccharide layer to form a solution including the polysaccharide and the metal nanoparticles; and
separating the metal nanoparticles from the polysaccharide.

2. The method of claim 1 , wherein the polysaccharide solution comprises chitosan and a solvent.

3. The method of claim 2 , wherein the polysaccharide solution further comprises an acid.

4. The method of claim 1 , wherein the metal salt includes noble metal cations selected from the group consisting of silver, palladium, platinum, gold, ruthenium, rhodium, osmium, and iridium.

5. The method of claim 1 , wherein the noble metal salt is a palladium metal salt.

6. The method of claim 5 , wherein the palladium metal salt is palladium nitrate.

7. The method of claim 5 , wherein the palladium metal salt is palladium chloride.

8. The method of claim 1 , wherein the predetermined concentration of the metal salt is from about 0.001 M to about 1 M.

9. The method of claim 1 , wherein the electrically conductive substrate is stainless steel.

10. The method of claim 1 , wherein the electric potential is a negative potential.

11. The method of claim 10 , wherein the negative potential is from about −0.5 volts to about −3 volts.

12. The method of claim 1 , wherein applying the electric potential further comprises using a three electrode assembly comprising the electrically conductive substrate, an Ag/AgCl reference electrode, and a counter electrode.

13. The method of claim 1 , wherein the predetermined period of time is from about 5 seconds to about 10 minutes.

14. The method of claim 1 , wherein an acid is used to dissolve the polysaccharide layer to form the solution including the polysaccharide and the metal nanoparticles.

15. The method of claim 1 , wherein the separating the metal nanoparticles from the polysaccharide includes filtration of the metal nanoparticles from the polysaccharide.

16. The method of claim 1 , wherein the metal nanoparticles have a diameter from about 3 nm to about 200 nm.

17. The method of claim 1 , wherein the metal nanoparticles have a diameter from about 15 nm to about 150 nm.

18. The method of claim 1 , wherein the metal nanoparticles have a diameter from about 50 nm to about 125 nm.

19. The method of claim 1 , further comprising recovering the metal nanoparticles by a method selected from the group consisting of plating, filtration, centrifuging, and combinations thereof.

Assignees

• Univ New York State Res Found

Inventors

• Halada Gary P
• Jha Prashant Kumar
• Cuiffo Michael A

Classifications

• B22F1/056

  Submicron particles having a size above 100 nm up to 300 nm · CPC title

• B22F1/054

  Nanosized particles · CPC title

• B22F9/24 Primary

  starting from liquid metal compounds, e.g. solutions · CPC title

• B22F2999/00

  Aspects linked to processes or compositions used in powder metallurgy · CPC title

• C25D15/00 Primary

  Electrolytic or electrophoretic production of coatings containing embedded materials, e.g. particles, whiskers, wires · CPC title