Method for producing small metal alloy nanoprticles

Patent metadata

Field	Value
Publication number	US-2016288212-A1
Application number	US-201414778480-A
Country	US
Kind code	A1
Filing date	Mar 24, 2014
Priority date	Mar 22, 2013
Publication date	Oct 6, 2016
Grant date	—

Abstract

A method for producing small metal alloy nanoparticles of a first metal and a second metal, comprising: mixing, at room temperature in air, a first aqueous solution of first and second metal nanoparticle precursor species in a first molar ratio of the first metal to the second metal; mixing a separate organic ligand into the first aqueous solution; adding a reducing agent to the first aqueous solution; and aging the first aqueous solution for a first period. The method may further comprise characterizing by photoluminescence or other property the metal alloy nanoparticles from the first aqueous solution and/or from a second aqueous solution of first and second metal nanoparticle precursor species in a second molar ratio of the first metal to the second metal.

First claim

What is claimed is:

1 . A method for producing small metal alloy nanoparticles of a first metal and a second metal, comprising:
mixing, at room temperature in air, a first aqueous solution of first and second metal nanoparticle precursor species in a first molar ratio of the first metal to the second metal; mixing a separate organic ligand into the first aqueous solution; adding a reducing agent to the first aqueous solution; and aging the first aqueous solution for a first period.

2 . The method of claim 1 further comprising: characterizing by photoluminescence or other property the metal alloy nanoparticles from the first aqueous solution.

3 . The method of claim 1 wherein the first metal nanoparticle precursor species comprises gold(III) chloride trihydrate (HAuCl4 3H2O), the second metal nanoparticle precursor species comprises copper(H) nitrate hemipentahydrate (Cu(NO3)2 5H2O), the organic ligand comprises poly(ethylene glycol) methyl ether thiol and the reducing agent comprises sodium borohydride (NaBH4).

4 . The method of claim 1 wherein the first metal nanoparticle precursor species comprises gold(III) chloride trihydrate (HAuCl4 3H2O), the second metal nanoparticle precursor species comprises silver nitrate (AgNO3), the organic ligand comprises poly(ethylene glycol) methyl ether thiol and the reducing agent comprises sodium borohydride (NaBH4).

5 . The method of claim 1 wherein each of the first and second metals is selected from the group consisting of gold, copper, silver, cobalt, nickel, iron and zinc.

6 . The method of claim 1 wherein the metal alloy nanoparticles comprise an alloy combination selected from the group consisting of Au—Co, Au—Ni, Au—Cu, Au—Fe, Au—Ag and Au—Zn.

7 . The method of claim 1 further comprising:
mixing, at room temperature in air, a second aqueous solution of the first and second metal nanoparticle precursor species in a second molar ratio of the first metal to the second metal;
mixing the separate organic ligand into the second aqueous solution;
adding the reducing agent to the second aqueous solution; and
aging the second aqueous solution for the first period.

8 . The method of claim 7 further comprising:
characterizing by photoluminescence or other property the metal alloy nanoparticles from the second aqueous solution; and
comparing the photoluminescence or other property of the metal alloy nanoparticles from the first and second aqueous solutions, respectively.

9 . The method of claim 1 wherein the metal alloy nanoparticles have a diameter ranging from about 1.8 nm to about 3 nm.

10 . A method for producing small metal alloy nanoparticles having increased photoluminescence in near infrared region comprising:
mixing, at room temperature in air, a plurality of aqueous solutions of first and second metal nanoparticle precursor species, wherein each of the plurality of solutions contains a different molar ratio of the first metal to the second metal; mixing a separate organic ligand into each of the aqueous solutions; reducing each of the solutions by addition of a reducing agent; and aging the reduced solutions for a first period.

11 . The method of claim 10 further comprising: characterizing by photoluminescence the resultant metal alloy nanoparticles produced from each of the plurality of aqueous solutions of different molar ratios of the first and second metals.

12 . The method of claim 10 wherein the first metal nanoparticle precursor species comprises gold(III) chloride trihydrate (HA u Cl 4 3H 2 O), the second metal nanoparticle precursor species comprises copper(II) nitrate hemipentahydrate (Cu(NO 3 ) 2 5 H2O), the organic ligand comprises poly(ethylene glycol) methyl ether thiol and the reducing agent comprises sodium borohydride (NaBH 4 ).

13 . The method of claim 10 wherein the first metal nanoparticle precursor species comprises gold(III) chloride trihydrate (HA u Cl 4 3H 2 O), the second metal nanoparticle precursor species comprises silver nitrate (AgNO 3 ), the organic ligand comprises poly(ethylene glycol) methyl ether thiol and the reducing agent comprises sodium borohydride (NaBH 4 ).

14 . The method of claim 10 wherein each of the first and second metals is selected from the group consisting of gold, copper, silver, cobalt, nickel, iron and zinc.

15 . The method of claim 10 wherein the metal alloy nanoparticles comprise an alloy combination selected from the group consisting of Au—Co, Au—Ni, Au—Cu, Au—Fe, Au—Ag and Au—Zn.

16 . The method of claim 10 wherein the metal alloy nanoparticles have a diameter ranging from about 1.8 nm to about 3 nm.

Assignees

• Univ Of Pittsburgh - Of The Commonwealth System Of Higher Education

Inventors

• Millstone Jill Erin
• Andolina Christopher Michael
• Dewar Andrew Craik

Classifications

• B22F1/054

  Nanosized particles · CPC title

• C22C9/00

  Alloys based on copper · CPC title

• B22F9/24 Primary

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

• C22C5/02

  Alloys based on gold · CPC title

• B82B3/0095

  Manufacture or treatments or nanostructures not provided for in groups B82B3/0009 - B82B3/009 · CPC title