Process to prepare metal nanoparticles or metal oxide nanoparticles

Patent metadata

Field	Value
Publication number	US-2018179653-A1
Application number	US-201715613613-A
Country	US
Kind code	A1
Filing date	Jun 5, 2017
Priority date	Jul 19, 2010
Publication date	Jun 28, 2018
Grant date	—

Abstract

The invention is directed to a process to prepare metal nanoparticles or metal oxide nanoparticles by applying a cathodic potential as an alternating current (ac) voltage to a solid starting metal object which solid metal object is in contact with a liquid electrolyte comprising a stabilising cation. The invention is also directed to the use of the nanoparticles as a catalyst.

First claim

1 . Process to prepare metal nanoparticles or metal oxide nanoparticles by applying a cathodic potential as an alternating current (ac) voltage to a solid starting metal object which solid metal object is in contact with a liquid electrolyte comprising a stabilising cation.

2 . Process according to claim 1 , wherein the liquid electrolyte comprises water.

3 . Process according to any one of claims 1 - 2 , wherein the metal or metals are chosen from the groups of the Periodic Table of Elements according to IUPAC starting at 3 to and including group 15.

4 . Process according to claim 3 , wherein the metal is chosen from the group consisting of Y, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ru, Ag, Ta, W, Re, Os, Ir, Pt, Au, Al, Si, Ga, Ge, As, In, Sn, Sb, Te, Tl, Pb and Bi.

5 . Process according to any one of claims 1 - 4 , wherein the solid starting metal is an alloy of two or more metals.

6 . Process according to claim 5 , wherein the alloy is chosen from the group consisting of PtNi, PtIr, PtRh, PtRu, PtCo, PtMo, PtAu, PtAg, PtRuMo, PtFe, AuCu, PtCu, PtOs, PtSn, PtBi, CuNi, CoNi, AgCu, AgAu, NiSn and SnAg, SnAgCu.

7 . Process according to claim 6 , wherein the alloy is a SnAg or SnAgCu alloy.

8 . Process according to any one of claims 1 - 7 , wherein the stabilising cation is an alkali, alkaline earth, ammonium or an alkyl ammonium cation.

9 . Process according to any one of claims 1 - 8 , wherein two electrodes are in contact with the liquid electrolyte and wherein one electrode is composed of the solid starting material and wherein only to said electrode a cathodic potential is applied.

10 . Process according to any one of claims 1 - 9 , wherein the nanoparticles are separated from the liquid electrolyte.

11 . Process according to claim 10 , wherein separation is performed by means of centrifugal force to obtain a phase rich in nanoparticles and a phase of electrolyte, re-using the electrolyte in the process according to claims 1 - 9 , diluting the phase rich in nanoparticles with water and redispersion by sonication.

12 . Use of the nanoparticles as obtained by the process according to any one of claims 1 - 11 as a catalyst.

13 . Use according to claim 12 as a catalyst in fuel-cell reactions.

14 . Use according to claim 13 as a catalyst in the oxidation of hydrogen, ethanol, formic acid, ammonia, borohydride and other organic compounds and the reduction of oxygen, nitrates and nitrites.

15 . Use according to claim 12 as a catalyst for neutralization of exhaust gases.

16 . Use according to claim 14 as a catalyst for waste water treatment.

17 . Use of the nanoparticles as obtained by the process according to any one of claims 1 - 11 as an electrochemical sensor.

18 . Use of the nanoparticles as obtained by the process according to any one of claims 1 - 11 in photovoltaics.

19 . Use of the nanoparticles as obtained by the process according to any one of claims 1 - 11 as part of a conductive nano ink.

20 . Use of silver nanoparticles as obtained by the process according to any one of claims 1 - 11 as part of an anti-microbial device or composition.

21 . Lead-free soldering paste comprising nanoparticles as obtained by the process according to any one of claims 7 - 11 .

Assignees

• Univ Leiden

Inventors

• Yanson Alexei
• Koper Marcus
• Rodriguez Paramaconi
• Garcia-Araez Nuria

Classifications

• B01J23/462

  Ruthenium · CPC title

• B23K35/025

  Pastes, creams or slurries · CPC title

• B01J23/89

  combined with noble metals · CPC title

• C25C5/00

  Electrolytic production, recovery or refining of metal powders or porous metal masses · CPC title

• B01D53/94

  by catalytic processes · CPC title