Method of making room temperature stable δ-phase bismuth(III) oxide

Patent metadata

Field	Value
Publication number	US-11186494-B2
Application number	US-202016832626-A
Country	US
Kind code	B2
Filing date	Mar 27, 2020
Priority date	Sep 29, 2017
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

Provided is room temperature stable δ-phase Bi2O3. Ion conductive compositions comprise at least 95 wt % δ-phase Bi2O3, and, at 25° C., the compositions are stable and have a conductivity of at least 10−7 S/cm. Related methods, electrochemical cells, and devices are also disclosed.

First claim

The invention claimed is:

1. A method of making an ion conductive composition comprising δ-phase Bi 2 O 3 , said method comprising heating Bi 2 O 3 to at least 730° C., then cooling the material to less than or equal to 400° C., wherein, during said cooling, the temperature of the material is reduced from 650° C. to less than or equal to 400° C. within 100 ms or less, thereby obtaining δ-phase Bi 2 O 3 wherein the composition comprises at least 95 wt % Bi 2 O 3 and, at 25° C., the composition is stable and has a conductivity of at least 10 −7 S/cm.

2. The method according to claim 1 , wherein said heating Bi 2 O 3 to at least 730° C. comprises heating the Bi 2 O 3 to at least 830° C.

3. The method according to claim 1 , wherein said cooling the material to less than or equal to 400° C. comprises cooling the material to less than or equal to 250° C.

4. The method according to claim 1 , comprising, during said cooling, the temperature of the material is reduced from 650° C. to less than 400° C. within 50 ms or less.

5. A method of making a bismuth oxide composition comprising heating a first Bi 2 O 3 material having a first phase to at least 730° C., then cooling the material to less than or equal to 400° C., wherein, during said cooling, the temperature of the material is reduced from 650° C. to less than or equal to 400° C. within 100 ms or less, to obtain a second Bi 2 O 3 material having a second phase.

6. A method according to claim 5 , wherein the second Bi 2 O 3 material having the second phase comprises a δ-phase Bi 2 O 3 .

7. A method according to claim 5 , wherein the first Bi 2 O 3 material having the first phase comprises an amorphous phase Bi 2 O 3 .

8. The method according to claim 5 , wherein the second Bi 2 O 3 material having the second phase is an ion conductive composition comprising at least 95 wt % Bi 2 O 3 and, at 25° C., the composition is stable and has a conductivity of at least 10 −7 S/cm.

9. The method according to claim 5 , wherein said composition is stable for at least one year at 25° C.

10. The method according to claim 5 , wherein the composition comprises greater than or equal to 99 wt % of the δ-phase Bi 2 O 3 .

11. The method according to claim 5 , wherein the composition comprises greater than 99.9 mole % of the δ-phase Bi 2 O 3 .

12. The method according to claim 5 , wherein the composition does not comprise titanium, manganese, lead, yttrium, or erbium.

13. The method according to claim 5 , wherein said composition is pinhole free.

14. The method according to claim 5 , wherein at least 99 vol % of said composition is pinhole free.

15. The method according to claim 5 , wherein the composition has a conductivity of 10 −7 to 10 −3 S/cm.

16. The method according to claim 5 , wherein said composition comprises substantially single phase Bi 2 O 3 that comprises less than 1 vol % and/or less than 1 wt % of any secondary Bi 2 O 3 phases.

17. The method according to claim 5 , wherein the composition has a grain size of 4 nm to 1,000,000 nm.

18. The method according to claim 5 , further comprising forming a film comprising the composition.

19. The method according to claim 18 , wherein the film has a thickness of 10 nm to 10,000 nm.

20. The method according to claim 5 , further comprising forming an electrochemical device comprising the composition.

21. The method according to claim 20 , wherein the composition is in the form of a monolithic film.

22. The method according to claim 20 , wherein said device comprises a solid oxide fuel cell (SOFC), an oxygen sensor, or a metal-air battery.

Assignees

• Univ Cornell

Inventors

• Bell Robert
• Murphy Marc
• Van Dover R Bruce
• Thompson Michael O
• Beaucage Peter A

Classifications

• H01M8/1266

  the electrolyte containing bismuth oxide · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M2300/0074

  Ion conductive at high temperature · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• C01P2006/40

  Electric properties · CPC title