Structured catalytic nanoparticles and method of preparation

• US 9,415,373 B2
• Filed: 03/08/2011
• Issued: 08/16/2016
• Est. Priority Date: 03/08/2010
• Status: Active Grant

• Current Assignee: Cerion, LLC (Revstone Industries LLC)
• Original Assignee: Cerion, LLC (Revstone Industries LLC)
• Inventors: DiFrancisco, Albert Gary, Reed, Kenneth J., Hailstone, Richard K., Prok, Gary R., Allston, Thomas D.
• Primary Examiner(s): Felton, Aileen B
• Application Number:
  US13/583,809
• Publication Number:
  US 20130109600A1
• Time in Patent Office: 1,988 Days
• US Class Current: 1/1
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/10 of rare earths
• CPC Class Codes: B01J 23/83 with rare earths or actinides
• CPC Class Codes: B01J 37/0221 of particles
• CPC Class Codes: B01J 37/031 Precipitation
• CPC Class Codes: B01J 37/035 Precipitation on carriers
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01F 17/235 Cerium oxides or hydroxides
• CPC Class Codes: C01F 17/32 oxide or hydroxide being the only anion, e.g. NaCeO2 or MgxCayEuO
• CPC Class Codes: C01G 49/00 Compounds of iron
• CPC Class Codes: C01G 49/009 Compounds containing, besides iron, two or more other elements, with the exception of oxygen or hydrogen
• CPC Class Codes: C01P 2002/52 containing elements as dopants
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2004/45 Aggregated particles or particles with an intergrown morphology
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C01P 2004/84 one phase coated with the other
• CPC Class Codes: C10L 1/1233 oxygen containing compounds, e.g. oxides, hydroxides, acids and salts thereof
• CPC Class Codes: C10L 10/02 for reducing smoke development
• CPC Class Codes: C10M 125/10 : Metal oxides, hydroxides, carbonates or bicarbonates
• CPC Class Codes: C10M 2201/062 : Oxides; Hydroxides; Carbonates or bicarbonates
• CPC Class Codes: C10N 2020/06 : Particles of special shape or size
• CPC Class Codes: C10N 2050/015 : Dispersions of solid lubricants
• CPC Class Codes: Y10S 977/775 : Nanosized powder or flake, e.g. nanosized catalyst
• CPC Class Codes: Y10S 977/811 : Of specified metal oxide composition, e.g. conducting or semiconducting compositions such as ITO, ZnOx
• CPC Class Codes: Y10S 977/89 : Deposition of materials, e.g. coating, cvd, or ald
• CPC Class Codes: Y10S 977/902 : Specified use of nanostructure

Abstract

A method of making a structured, doped, cerium oxide nanoparticle includes (a) forming a first reaction mixture including cerium(III), an optional metal ion other than cerium, a base, a stabilizer, and a solvent, (b) contacting the first reaction mixture with an oxidant, (c) forming a cerium oxide nanoparticle core by heating the product of step (b), (d) forming a second reaction mixture by combining with the first reaction mixture one or more metal ions other than cerium, and an optional additional quantity of cerium(III), and (e) forming a shell surrounding the core of cerium oxide by heating the second reaction mixture to produce a product dispersion of structured cerium oxide nanoparticles.

Claims

1. A method of making a structured, doped, cerium oxide nanoparticle, comprising:

a. forming a first reaction mixture comprising cerium(III), an optional metal ion other than cerium, a base, a stabilizer, and a solvent;

b. contacting said first reaction mixture with an oxidant;

c. forming a cerium oxide nanoparticle core by heating the product of step b);

d. forming a second reaction mixture by combining with the first reaction mixture one or more metal ions other than cerium, and an optional additional quantity of cerium(III); and

e. forming a shell partially or continuously surrounding said core of cerium oxide by heating said second reaction mixture to produce a product dispersion of structured cerium oxide nanoparticles.

2. The method of claim 1, wherein the first reaction mixture further comprises one or more metal ions other than cerium;

and wherein the identity and/or relative quantity of metal ions differs from that of the second reaction mixture.

3. The method of claim 1, wherein step d) further comprises addition of cerium (III) ions and oxidant.

4. The method of claim 1, wherein the heating of step c) or step e) raises the reaction mixture to about 50°

C. to 100°

C.

5. The method of claim 1, wherein the addition of metal ions in step d) is performed concurrently with the addition of the oxidant in step b).

6. The method of claim 5, wherein the introduction of the metal ions commences at about the midpoint of the introduction of the oxidant.

7. The method claim 1, further comprising a step of diluting or concentrating the product dispersion of step e).

8. The method claim 1, further comprising a step of diafiltration of the product dispersion to less than 10 mSiemens.

9. The method claim 7, further comprising a step of diafiltration of the product dispersion to less than 10 mSiemens.

10. The method claim 1, wherein the stabilizer is an alkoxylated carboxylic acid.

11. The method of claim 10, wherein the alkoxylated carboxylic acid is methoxyacetic acid.

12. The method of claim 1, wherein the base is ammonium hydroxide.

13. The method of claim 1, wherein the oxidant is air, molecular oxygen or hydrogen peroxide.

14. The method of claim 1, wherein the metal ion other than cerium are selected from the group consisting of ions of:

Li, Mg, Sc, Ti, V, Cr, Zr, Mn, Fe, Co, Ni, Cu, Ag, Au, Bi, Pd, Pt, Pr, Gd, Sm, Y, La, and combinations thereof.

15. The method of claim 1, wherein the metal ion other than cerium is an ion of a transition metal.

16. The method of claim 1, wherein the amount of metal ion other than cerium in steps a) and d) are equal.

17. The method of claim 15, wherein the metal ion other than cerium is an ion of iron, zirconium, or a combination thereof.

18. The method of claim 17, wherein the metal ion other than cerium is iron;

and the quantity of iron ion added in step d) is greater than that added in step a).

19. The method of claim 17, wherein the metal ion other than cerium added in step d) consists essentially of iron ion.

20. The method of claim 17, wherein zirconium ion is the metal ion other than cerium, and the amount added in step d) is greater than that in step a).

21. The method of claim 17, wherein zirconium ion is the metal ion other than cerium, and the amount added in step d) is less than that in step a).