Synthesis of cerium oxide nanorods

Patent metadata

Field	Value
Publication number	US-9738541-B2
Application number	US-201414515493-A
Country	US
Kind code	B2
Filing date	Oct 15, 2014
Priority date	Jan 29, 2013
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

Cerium oxide nanorods having a variety of aspect ratios can be produced by providing a first mixture that includes a cerium precursor material, and using microwave to heat the first mixture to a first temperature for a period of time to produce first plurality of cerium oxide nanorods having a first range of aspect ratios. A second mixture that includes a cerium precursor material heated using microwave to a second temperature for a period of time to produce second plurality of cerium oxide nanorods having a second range of aspect ratios. The first plurality of cerium oxide nanorods and the second plurality of cerium oxide nanorods are mixed to produce third plurality of cerium oxide nanorods having the third range of aspect ratios that is broader than the first range or the second range.

First claim

What is claimed is:

1. A method of fabricating cerium oxide nanorods, the method comprising:
receiving input specifying an aspect ratio that is greater than 20 or a length that is greater than 200 nm;
accessing information that maps aspect ratios and lengths to temperatures, the information including mapping aspect ratios greater than 20 to temperatures, and mapping lengths greater than 200 nm to temperatures, and based on the information, mapping the input aspect ratio or length to a specified temperature; and
using microwave to heat a mixture that includes a cerium precursor material to the specified temperature and produce a plurality of cerium oxide nanorods having aspect ratios or lengths that correspond to the input aspect ratio or length.

2. The method of claim 1 , comprising mixing a cerium sulfate precursor and sodium hydroxide to produce the mixture that includes the cerium precursor material.

3. The method of claim 1 in which producing the plurality of cerium oxide nanorods comprises producing fluorite structured cerium oxide nanorods.

4. The method of claim 1 in which heating the mixture to the specified temperature comprises heating the mixture to a temperature in a range from 80° C. to 200° C.

5. The method of claim 1 in which producing the plurality of cerium oxide nanorods comprising producing a plurality of cerium oxide nanorods having a range of aspect ratios from 20:1 to 60:1.

6. The method of claim 1 in which the information includes information about a first aspect ratio that maps to a first temperature, and a second aspect ratio that maps to a second temperature, and the first aspect ratio is greater than the second aspect ratio by at least 50%.

7. The method of claim 1 in which the information includes information about a first aspect ratio that maps to a first temperature, and a second aspect ratio that maps to a second temperature, and the first aspect ratio is greater than at least twice the second aspect ratio.

8. The method of claim 1 in which the information includes information about a first aspect ratio that maps to a first temperature, and a second aspect ratio that maps to a second temperature, and the first aspect ratio is greater than at least three times the second aspect ratio.

9. The method of claim 1 in which the information includes information about a first length that maps to a first temperature, and a second length that maps to a second temperature, and the first length is greater than the second length by at least 50%.

10. The method of claim 1 in which the information includes information about a first length that maps to a first temperature, and a second length that maps to a second temperature, and the first length is greater than at least twice the second length.

11. The method of claim 1 in which the information includes information about a first length that maps to a first temperature, and a second length that maps to a second temperature, and the first length is greater than at least three times the second length.

12. The method of claim 1 , comprising after heating the mixture, cooling the mixture, filtering the mixture, and drying the mixture to produce the plurality of cerium oxide nanorods.

13. The method of claim 1 in which the aspect ratio is greater than 25.

14. The method of claim 1 in which the aspect ratio is greater than 30.

15. The method of claim 1 in which the aspect ratio is greater than 35.

16. The method of claim 1 in which the length is greater than 300 nm.

17. The method of claim 1 in which the length is greater than 400 nm.

18. The method of claim 1 in which the length is greater than 500 nm.

19. The method of claim 1 in which the length is greater than 600 nm.

20. The method of claim 1 in which the length is greater than 700 nm.

21. The method of claim 1 in which the length is greater than 800 nm.

22. The method of claim 1 in which the length is greater than 900 nm.

23. The method of claim 1 in which the length is greater than 1000 nm.

24. The method of claim 1 in which the length is greater than 1100 nm.

25. The method of claim 1 in which the length is greater than 1200 nm.

26. The method of claim 1 in which the length is greater than 1300 nm.

27. The method of claim 1 in which the length is greater than 1400 nm.

28. The method of claim 1 in which the length is greater than 1500 nm.

29. The method of claim 1 in which the length is greater than 1600 nm.

30. The method of claim 1 in which the length is greater than 1700 nm.

31. The method of claim 1 in which the length is greater than 1800 nm.

32. The method of claim 1 in which the length is greater than 1900 nm.

33. The method of claim 1 in which the length is greater than 2000 nm.

34. The method of claim 1 , comprising:
receiving a second input specifying a second aspect ratio or a second length;
accessing information that maps aspect ratios and lengths to temperatures, and based on the information, mapping the second input aspect ratio or second length to a second specified temperature;
using microwave to heat a second mixture that includes a cerium precursor material to the second specified temperature and produce a second plurality of cerium oxide nanorods having second aspect ratios or second lengths that correspond to the second input aspect ratio or length; and
compressing the plurality of cerium oxide nanorods and the second plurality of cerium oxide nanorods into a compressed format such that the cerium oxide nanorods in the compressed format have at least one of various lengths or various aspect ratios.

35. The method of claim 1 in which accessing information that maps aspect ratios and lengths to temperatures comprises using a controller to access a storage device that has information including mapping aspect ratios greater than 20 to temperatures, and mapping lengths greater than 200 nm to temperatures.

36. The method of claim 35 in which mapping the input aspect ratio or length to a specified temperature comprises using the controller to look up the table and map the input aspect ratio or length to a specified temperature.

37. The method of claim 36 in which using microwave to heat a mixture comprises using the controller to configure a microwave heater to heat the mixture of the cerium precursor material to the specified temperature.

38. A method of fabricating cerium oxide nanorods, the method comprising:
receiving input specifying an aspect ratio or a length;
accessing information that maps aspect ratios and lengths to temperatures that are achieved by microwave heating, the information indicating that the length and aspect ratio increase as the temperature increases, and based on the information, mapping the input aspect ratio or length to a specified temperature; and
using microwave to heat a mixture that includes a cerium precursor material to the specified temperature and produce a plurality of cerium oxide nanorods having aspect ratios or lengths that correspond to the input aspect ratio or length.

39. The method of claim 38 in which the information includes mapping aspect ratios greater than 20 to temperatures, and mapping lengths greater than 200 nm to t

Assignees

• Nutech Ventures

Inventors

• Cheung Chin Li
• Gernhart Zane Charles

Classifications

• B01J37/346 Primary

  of microwave energy · CPC title

• C01P2006/12

  Surface area · CPC title

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title

• C01P2004/54

  Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension · CPC title

• B01J23/10

  of rare earths · CPC title