Nanoparticles for the use as pinning centers in superconductors

Patent metadata

Field	Value
Publication number	US-10450199-B2
Application number	US-201615554742-A
Country	US
Kind code	B2
Filing date	Feb 24, 2016
Priority date	Mar 2, 2015
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

The present invention is in the field of nanoparticles, their preparation and their use as pinning centers in superconductors. In particular the present invention relates to nanoparticles comprising an oxide of Sr, Ba, Y, La, Ti, Zr, Hf, Nb, or Ta, wherein the nanoparticles have a weight average diameter of 1 to 30 nm and wherein an organic compound of general formula (I), (II) or (III) or an organic compound containing at least two carboxylic acid groups on the surface of the nanoparticles (I) (II) (III) wherein a is 0 to 5, b and c are independent of each other 1 to 14, n is 1 to 5, f is 0 to 5, p and q are independent of each other 1 to 14, and e and f are independent of each other 0 to 12.

First claim

The invention claimed is:

1. Nanoparticles, comprising:
an oxide of at least one element selected from the group consisting of Sr, Ba, Y, La, Ti, Zr, Hf, Nb, and Ta,
wherein:
the nanoparticles have a weight average diameter of 1 to 30 nm; and
an organic compound of general formula (I), (II) or (III) is on the surface of the nanoparticles:

wherein:
a is 0 to 5;
b and c are independent of each other 1 to 14;
n is 1 to 5;
r is 0 to 5;
p and q are independent of each other 1 to 14;
e is 0 to 12; and
f is 2 to 6.

2. The nanoparticles according to claim 1 , wherein the nanoparticles comprise ZrO 2 , HfO 2 or Ta 2 O 5 .

3. The nanoparticles according to claim 1 , wherein a trialkyl phosphorous oxide or a fatty acid is additionally on the surface of the nanoparticles.

4. The nanoparticles according to claim 1 , wherein the nanoparticles are crystalline.

5. The nanoparticles according to claim 1 , wherein the nanoparticles have a dispersity of particle size distribution D 90 /D 50 measured by dynamic light scattering of 1.2 or less.

6. A process for producing the nanoparticles of claim 1 , the process comprising:
(i) precipitating nanoparticles comprising the oxide of at least one element selected from the group consisting of Sr, Ba, Y, La, Ti, Zr, Hf, Nb, and Ta from a suspension comprising a non-polar solvent, wherein the nanoparticles have a weight average diameter of 1 to 30 nm; and
(ii) adding an alcohol and the organic compound of general formula (I), (II) or (III) to the precipitated nanoparticles, to obtain the nanoparticles.

7. The process according to claim 6 , wherein the suspension comprising a non-polar solvent and nanoparticles is produced by a condensation or esterification reaction comprising a soluble precursor in the presence of a surfactant.

8. An ink for the preparation of a high temperature superconductor, the ink comprising:
(a) an yttrium or rare earth metal-containing compound;
(b) an alkaline earth metal-containing compound;
(c) a transition metal-containing compound;
(d) an alcohol; and
(e) the nanoparticles of claim 1 .

9. The ink according to claim 8 , wherein the alcohol is a mixture of methanol and C 2 to C 12 , alcohols.

10. The ink according to claim 8 , wherein at least one of the rare earth metal-containing compound or the yttrium-containing compound, the alkaline earth metal-containing compound and the transition metal-containing compound contains fluorine.

11. The ink according to claim 8 , comprising the nanoparticles at a concentration at which a molar ratio of metal in the nanoparticles to the yttrium-containing compound or the rare earth metal-containing compound is 1 to 30 %.

12. A superconductor, comprising the nanoparticles of claim 1 as pinning centers in the superconductors.

Assignees

• Basf Se

Inventors

• Hemgesberg Maximilian
• Schwall Denis
• Staudt Thorsten Martin
• Driessche Isabel Van
• De Keukeleere Katrien
• De Roo Jonathan
• Gruendling Till
• Maier Matthias
• Baecker Michael
• Bennewitz Jan
• Feenstra Ron
• Rijckaert Hannes
• Zeger Hens

Classifications

• C09C1/3669

  Treatment with low-molecular organic compounds · CPC title

• C09C1/00

  Treatment of specific inorganic materials other than fibrous fillers (tenebrescent materials C09K9/00; luminescent materials C09K11/00); Preparation of carbon black · CPC title

• C01P2004/52

  highly monodisperse size distribution · CPC title

• C01P2002/74

  by peak-intensities or a ratio thereof only · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title