Material fuel cell separator, fuel cell separator using same, fuel cell stack, and method of producing fuel cell separator material
View Patent ↗A material for fuel cell separator, wherein a surface layer 6 containing Au and Cr is formed on a surface of a Ti base 2 , and an intermediate layer 2 a containing Ti, O, Cr, and less than 20 atomic % of Au is present between the Ti base and the surface layer, a thickness of an area containing 65 atomic % or more of Au being 1.5 nm or more, a maximum concentration of Au being 80 atomic % or more, a coating amount of Au being 9000 to 40000 ng/cm 2 , a ratio represented by (Au coating amount)/(Cr coating amount) being 10 or more, a coating amount of Cr being 200 ng/cm 2 or more, and in the intermediate layer having an area containing 10% or more of Ti, 10% or more of O and 20% or more of Cr being 1 nm or more.
1. A material for a fuel cell separator, comprising:
(a) a Ti base;
(b) a surface layer containing Au and Cr formed on a surface of the Ti base; and
(c) an intermediate layer containing Ti, O, Cr, and less than 20 atomic % of Au, wherein the intermediate layer is present between the Ti base and the surface layer;
wherein an area of the surface layer containing 65 atomic % or more of Au has a thickness of 1.5 nm to 27 nm,
a maximum concentration of Au in the surface layer is 85 to 99 weight %,
a coating amount of Au is 9000 to 40000 ng/cm 2 ,
a ratio represented by (Au coating amount)/(Cr coating amount) is 10 to 80.4,
a coating amount of Cr is 200 ng/cm 2 to 5040 ng/cm 2 , and
the intermediate layer has an area of 1 nm to 5 nm containing 10 atomic % or more of Ti, 10 atomic % or more of 0 and 20 atomic % or more of Cr.
2. The material for a fuel cell separator according to claim 1 , wherein the Ti base is formed by coating a Ti coating with a thickness of 10 nm or more on a material other than Ti.
3. A polymer electrolyte fuel cell comprising the material for a fuel cell separator according to claim 1 .
4. A direct methanol fuel cell comprising the material for a fuel cell separator according to claim 1 .
5. A fuel cell separator comprising the material for a fuel cell separator according to claim 1 , wherein a reaction gas flow path and/or a reaction liquid flow path is press-formed on the Ti base, and then the surface layer is formed.
6. A fuel cell separator comprising the material for a fuel cell separator according to claim 1 , wherein the surface layer is formed on the Ti base, and then a reaction gas flow path and/or a reaction liquid flow path is press-formed.
7. A fuel cell stack comprising the material for a fuel cell separator according to claim 1 .
8. A method of producing the material for a fuel cell separator according to claim 1 , comprising:
dry film-forming Cr on the surface of the Ti base, and
dry film-forming Au thereon.
9. The method of producing the material for a fuel cell separator according claim 8 , wherein the dry film-forming is sputtering.
10. A fuel cell stack comprising the fuel cell separator according to claim 5 .
11. A fuel cell stack comprising the fuel cell separator according to claim 6 .