Materials for ammonia synthesis

Patent metadata

Field	Value
Publication number	US-12012662-B2
Application number	US-202318307289-A
Country	US
Kind code	B2
Filing date	Apr 26, 2023
Priority date	Jan 14, 2019
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

Disclosed herein are doped perovskite oxides. The doped perovskite oxides may be used as a cathode material in an electrochemical cell to electrochemically generate ammonia from N 2 . The doped perovskite oxides may be combined with nitride compounds, for instance iron nitride, to further increase the efficiency of the ammonia production.

First claim

What is claimed is:

1. A method of generating ammonia, comprising:
electrochemically reducing H 2 O and N 2 with a composition comprising a perovskite oxide, to provide NH 3 and O 2 - ; and
oxidizing the O 2 1 to give oxygen gas,
wherein the perovskite oxide has the formula:
A 1 w A 2 x X y Fe z O 3 ,

wherein:
A 1 is selected from La, Tb, Gd, Sm, Pr, and Nd;
A 2 is selected from Sr, Mg, Ca, and Ba;
X is one or more metals in the +1 or +2 oxidation state;
w is from 0.5-1.0;
x is from 0-0.5;
y is from 0-0.5; and
z is from 0.5 to less than 1.0;
wherein w, x, y, and z are chosen to maintain electroneutrality, and
wherein w, x, y, and z are chosen to maintain electroneutrality, and wherein the composition further comprises one or more nitride compounds having the formula M a N b , wherein M is selected from Fe, Mb, Co, Cr, and V, a is selected from 1, 2, 3, or and 4, and b is selected from 1, 2, 3, and 4.

2. The method of claim 1 , wherein the electrochemical reduction is performed by supplying an electric current to the perovskite oxide of claim 1 , wherein the current applied is in an amount from 0.1-50 mA.

3. The method of claim 1 , wherein X is Ni, Co, Ti, Mn, Zn, Cu, Li, Al, Sc, V, Cr, Ga, Ge, Y, Zr, Nb, In, V, W, Mb, Pd, Pt, Ag, Au, Cd, or a combination thereof.

4. The method of claim 1 , wherein A 1 is La.

5. The method of claim 1 , wherein A 2 is Sr.

6. The method of claim 1 , wherein w is from 0.6 to 0.9.

7. The method of claim 1 , wherein z is from 0.6 to 0.9.

8. The method of claim 1 , wherein X is Ni or Co.

9. The method of claim 1 , wherein x is from 0.15 to 0.25.

10. The method of claim 1 , wherein y is from 0.15 to 0.25.

11. The method of claim 1 , wherein M is Fe.

12. The method of claim 1 , wherein the weight ratio of perovskite oxide to nitride compound is from 10:1 to 1:10.

Assignees

• Ohio State Innovation Foundation

Inventors

• Ozkan Umit
• Gunduz Seval
• Deka Dhruba Jyoti

Classifications

• C25B13/07

  based on ceramics · CPC title

• C25B1/27

  Ammonia · CPC title

• C25B9/19 Primary

  with diaphragms · CPC title

• C25B9/23

  comprising ion-exchange membranes in or on which electrode material is embedded · CPC title

• C01G49/009

  Compounds containing iron, with or without oxygen or hydrogen, and containing two or more other elements · CPC title