Proton conductor, cell structure, methods for producing proton conductor and cell structure, fuel cell, and water electrolysis device

Patent metadata

Field	Value
Publication number	US-2018375114-A1
Application number	US-201616061888-A
Country	US
Kind code	A1
Filing date	Dec 16, 2016
Priority date	Dec 18, 2015
Publication date	Dec 27, 2018
Grant date	—

Abstract

A proton conductor contains a metal oxide having a perovskite structure and represented by A a B b M c O 3-δ (wherein: A is at least one of Ba, Ca, and Sr; B is at least one of Ce and Zr; M is at least one of Y, Yb, Er, Ho, Tm, Gd, and Sc; 0.85≤a≤1; 0.5≤b<1; c=1-b; and δ is an oxygen deficiency amount), and a standard deviation in a triangular diagram representing an atomic composition ratio of the A, the B, and the M is not greater than 0.04.

First claim

1 : A proton conductor containing a metal oxide having a perovskite structure and represented by formula (1):
A a B b M c O 3-δ   (1)
(wherein: A is at least one element selected from the group consisting of Ba, Ca, and Sr; B is at least one element selected from the group consisting of Ce and Zr; M is at least one element selected from the group consisting of Y, Yb, Er, Ho, Tm, Gd, In, and Sc; “a” is a number that satisfies 0.85≤a≤1; “b” is a number that satisfies 0.5≤b<1; “c” is a number that satisfies c=1-b; and δ is an oxygen deficiency amount), wherein a standard deviation in a triangular diagram representing an atomic composition ratio of the A, the B, and the M contained in the proton conductor is not greater than 0.04.

2 : The proton conductor according to claim 1 , wherein
in the formula (1), the A contains Ba, the B contains Zr, and the M contains Y.

3 : The proton conductor according to claim 1 , wherein the standard deviation in the triangular diagram representing the atomic composition ratio of the A, the B, and the M contained in the proton conductor is not greater than 0.037.

4 : A method for producing a proton conductor containing a metal oxide having a perovskite structure and represented by formula (1):
A a B b M c O 3-δ   (1)
(wherein: A is at least one element selected from the group consisting of Ba, Ca, and Sr; B is at least one element selected from the group consisting of Ce and Zr; M is at least one element selected from the group consisting of Y, Yb, Er, Ho, Tm, Gd, In, and Sc; “a” is a number that satisfies 0.85≤a≤1; “b” is a number that satisfies 0.5≤b<1; “c” is a number that satisfies c=1-b; and δ is an oxygen deficiency amount), the method comprising: a preparation step of preparing a material containing an element represented by the A, an element represented by the B, and an element represented by the M, at a ratio that satisfies the “a”, the “b”, and the “c”; and a firing step of firing the material at a first firing temperature of 1500° C. or higher for 20 hours or longer.

5 : The method for producing the proton conductor according to claim 4 , further comprising a preliminary firing step of preliminarily firing the material at a temperature less than 1500° C., after the preparation step and before the firing step.

6 : The method for producing the proton conductor according to claim 5 , further comprising a pulverization step of pulverizing the preliminarily fired material, after the preliminary firing step and before the firing step.

7 : The method for producing the proton conductor according to claim 4 , wherein the first firing temperature is not lower than 1600° C.

8 : A cell structure comprising:
a cathode; an anode; and a solid electrolyte layer interposed between the cathode and the anode and having proton conductivity, wherein the anode contains the proton conductor according to claim 1 and a nickel compound.

9 : A method for producing a cell structure, the method comprising:
a step of preparing a cathode material, a solid electrolyte material having proton conductivity, and an anode material; a step of laminating a layer containing the anode material and a layer containing the solid electrolyte material and then firing an obtained laminated body at a second firing temperature to form a joined body of an anode and a solid electrolyte layer; and a step of laminating a layer containing the cathode material, on a surface of the solid electrolyte layer and firing an obtained laminated body to form a cathode, wherein the anode material contains a proton conductor and a nickel compound, and the proton conductor is the proton conductor according to claim 1 .

10 : A method for producing a cell structure, the method comprising:
a step of preparing a cathode material, a solid electrolyte material having proton conductivity, and an anode material; a step of laminating a layer containing the anode material and a layer containing the solid electrolyte material and then firing an obtained laminated body at a third firing temperature to form a joined body of an anode and a solid electrolyte layer; and a step of laminating a layer containing the cathode material, on a surface of the solid electrolyte layer and firing an obtained laminated body to form a cathode, wherein the anode material contains a proton conductor and a nickel compound, and the proton conductor contains a metal oxide having a perovskite structure and represented by formula (1):
A a B b M c O 3-δ   (1)

(wherein: A is at least one element selected from the group consisting of Ba, Ca, and Sr; B is at least one element selected from the group consisting of Ce and Zr; M is at least one element selected from the group consisting of Y, Yb, Er, Ho, Tm, Gd, In, and Sc; “a” is a number that satisfies 0.85≤a≤1; “b” is a number that satisfies 0.5≤b<1; “c” is a number that satisfies c=1-b; and δ is an oxygen deficiency amount) and is obtained by firing a material containing an element represented by the A, an element represented by the B, and an element represented by the M at a ratio that satisfies the “a”, the “b”, and the “c”, at a first firing temperature of 1500° C. or higher for 20 hours or longer.

11 : The method for producing the cell structure according to claim 10 , wherein the first firing temperature is higher than the third firing temperature.

12 : A fuel cell comprising an anode containing the proton conductor according to claim 1 .

13 : A water electrolysis device comprising an anode containing the proton conductor according to claim 1 .

Assignees

• Sumitomo Electric Industries
• Univ Kyoto

Inventors

• Higashino Takahiro
• Noda Yohei
• Miyamoto Kazunari
• Hiraiwa Chihiro
• Mizuhara Naho
• Tawarayama Hiromasa
• Takeuchi Hisao
• Majima Masatoshi
• Uda Tetsuya
• Han Donglin
• Onishi Takayuki
• Otani Yuki

Classifications

• H01M8/10

  Fuel cells with solid electrolytes · CPC title

• H01M4/8885

  Sintering or firing · CPC title

• H01M4/9033

  Complex oxides, optionally doped, of the type M1MeO3, M1 being an alkaline earth metal or a rare earth, Me being a metal, e.g. perovskites · CPC title

• H01B1/08

  oxides · CPC title

• C01G25/006

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