Oxygen-reducing catalyst layer
An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.
1. An oxygen-reducing catalyst layer comprising:
a thermally stable substrate; and
a catalytic material film disposed on the thermally stable substrate, the catalytic material film comprising carbon, nitrogen, and a transition metal selected from the group consisting of iron, cobalt, and combinations thereof, wherein the oxygen-reducing catalyst layer exhibits catalytic activity of at least about 0.02 mA/cm 2 at 0.6 volts versus a reversible hydrogen electrode, and is corrosion resistant;
wherein the catalytic material film has an atomic composition that includes from about 50.0% to about 99.8% of the carbon, from about 0.1% to about 45.0% of the nitrogen, and from about 0.1% to about 15.0% of the transition metal.
2. The oxygen-reducing catalyst layer of claim 1 , wherein the catalytic material film comprises a physical vapor deposition film.
3. The oxygen-reducing catalyst layer of claim 1 , wherein the atomic composition includes from about 80.0% to about 95.0% of the carbon.
4. The oxygen-reducing catalyst layer of claim 1 , wherein the atomic composition includes from about 4.0% to about 20.0% of the nitrogen.
5. The oxygen-reducing catalyst layer of claim 1 , wherein the atomic composition includes from about 2.0% to about 10.0% of the transition metal.
6. The oxygen-reducing catalyst layer of claim 1 , wherein the catalytic material film is substantially free of platinum.
7. The oxygen-reducing catalyst layer of claim 6 , wherein the catalytic material film is substantially free of precious metals.
8. The oxygen-reducing catalyst layer of claim 1 , wherein the thermally stable substrate is selected from the group consisting of nanostructured thin film substrates, microstructured thin film substrates, carbon-containing substrates, carbon non-woven fabrics, titanium suboxide ceramic films, nano-tin oxide fins, nano-titanium oxide films, and combinations thereof.
9. The oxygen-reducing catalyst layer of claim 1 , wherein the catalytic material is thermally treated.
10. An oxygen-reducing catalyst layer comprising:
a thermally stable substrate; and
a catalytic material film disposed on the thermally stable substrate, the catalytic material film having an atomic composition that includes from about 50.0% to about 99.8% of carbon, from about 0.1% to about 45.0% of nitrogen, and from about 0.1% to about 15.0% of a transition metal selected from the group consisting of iron, cobalt, and combinations thereof.
11. The oxygen-reducing catalyst layer of claim 10 , wherein the catalytic material film comprises a physical vapor deposition film.
12. The oxygen-reducing catalyst layer of claim 10 wherein the atomic composition includes from about 80.0% to about 95.0% of the carbon.
13. The oxygen-reducing catalyst layer of claim 10 , wherein the atomic composition includes from about 4.0% to about 20.0% of the nitrogen.
14. The oxygen-reducing catalyst layer of claim 10 , wherein the atomic composition includes from about 2.0% to about 10.0% of the transition metal.
15. The oxygen-reducing catalyst layer of claim 10 , wherein the catalytic material film is substantially free of platinum.
16. The oxygen-reducing catalyst layer of claim 15 , wherein the catalytic material film is substantially free of precious metals.
17. The oxygen-reducing catalyst of claim 10 , wherein the thermally stable substrate is selected from the group consisting of nanostructured thin film substrates, microstructured thin film substrates, carbon-containing substrates, carbon non-woven fabrics, titanium suboxide ceramic films, nano-tin oxide fins, nano-titanium oxide films, and combinations thereof.
18. A membrane electrode assembly comprising:
a proton exchange membrane having a first surface;
an oxygen-reducing catalyst layer disposed adjacent the first surface of the proton exchange membrane comprising:
a thermally stable substrate; and
a catalytic material film disposed on the thermally stable substrate, the catalytic material film having an atomic composition comprising from about 50.0% to about 99.8% of carbon, from about 0.1% to about 45.0% of nitrogen, and from about 0.1% to about 15.0% of a transition metal selected from the group consisting of iron, cobalt, and combinations thereof.
19. The oxygen-reducing catalyst layer of claim 18 , wherein the catalytic material film comprises a physical vapor deposition film.
20. The membrane electrode assembly of claim 18 , wherein the catalytic material film is thermally treated.
21. The oxygen-reducing catalyst layer of claim 18 , wherein the catalytic material film is substantially free of platinum.
22. The oxygen-reducing catalyst layer of claim 21 , wherein the catalytic material film is substantially free of precious metals.
23. The membrane electrode assembly of claim 18 , wherein the thermally stable substrate is selected from the group consisting of nanostructured thin film substrates, microstructured thin film substrates, carbon-containing substrates, carbon non-woven fabrics, titanium suboxide ceramic films, nano-tin oxide fins, nano-titanium oxide films, and combinations thereof.