Materials for ammonia synthesis

Patent metadata

Field	Value
Publication number	US-2023287585-A1
Application number	US-202318307289-A
Country	US
Kind code	A1
Filing date	Apr 26, 2023
Priority date	Jan 14, 2019
Publication date	Sep 14, 2023
Grant date	—

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

1 - 18 . (canceled)

19 . 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.

20 . The method of claim 19 , 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.

21 . The method of claim 19 , 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.

22 . The method of claim 19 , wherein A 1 is La.

23 . The method of claim 19 , wherein A 2 is Sr.

24 . The method of claim 19 , wherein w is from 0.6 to 0.9.

25 . The method of claim 19 , wherein z is from 0.6 to 0.9.

26 . The method of claim 19 , wherein X is Ni or Co.

27 . The method of claim 19 , wherein x is from 0.15 to 0.25.

28 . The method of claim 19 , wherein y is from 0.15 to 0.25.

29 . The method of claim 19 , 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.

30 . The method of claim 29 , wherein M is Fe.

31 . The method of claim 29 , 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

• C25B11/069 Primary

  consisting of at least one single element and at least one compound; consisting of two or more compounds · CPC title

• C04B35/2633

  containing barium, strontium or calcium · CPC title