Supported nickel catalysts used as direct internal reforming catalyst in molten carbonate fuel cells
Disclosed here is a supported catalyst comprising a thermally stable core, wherein the thermally stable core comprises a metal oxide support and nickel disposed in the metal oxide support, wherein the metal oxide support comprises at least one base metal oxide and at least one transition metal oxide or rare earth metal oxide mixed with or dispersed in the base metal oxide. Optionally the supported catalyst can further comprise an electrolyte removing layer coating the thermally stable core and/or an electrolyte repelling layer coating the electrolyte removing layer, wherein the electrolyte removing layer comprises at least one metal oxide, and wherein the electrolyte repelling layer comprises at least one of graphite, metal carbide and metal nitride. Also disclosed is a molten carbonate fuel cell comprising the supported catalyst as a direct internal reforming catalyst.
1. A supported catalyst comprising:
a thermally stable core, comprising a metal oxide support and nickel disposed in the metal oxide support, wherein the metal oxide support comprises at least one base metal oxide and at least one transition metal oxide or rare earth metal oxide mixed with or dispersed in the base metal oxide; and
at least one electrolyte repelling layer coating the thermally stable core to form a core-shell structure, wherein the electrolyte repelling layer comprises at least one of graphite, metal carbide, and/or metal nitride.
2. The supported catalyst of claim 1 , wherein the metal oxide support has a surface area within a range of 5 to 120 m 2 /g.
3. The supported catalyst of claim 1 , wherein the base metal oxide comprises at least one alkaline metal oxide or post-transition metal oxide.
4. The supported catalyst of claim 1 , wherein the base metal oxide comprises at least one of alumina, CaO, and/or MgO.
5. The supported catalyst of claim 1 , wherein the metal oxide support comprises at least two different transition metal oxides and/or rare earth metal oxides in addition to the base metal oxide.
6. The supported catalyst of claim 1 , wherein an amount of the transition metal oxide and the rare earth metal oxide is within a range of 1 to 20 wt. % of the supported catalyst.
7. The supported catalyst of claim 1 , wherein an amount of the nickel is within a range of 10 to 50 wt. % of the supported catalyst.
8. The supported catalyst of claim 1 , wherein the supported catalyst has a mean pore diameter within a range of 65 to 700 Å, as measured by mercury porosimetry of pelletized catalyst, and has a pore size distribution characterized by a standard deviation of less than 10% of the mean pore diameter.
9. The supported catalyst of claim 1 , further comprising an electrolyte removing layer.
10. The supported catalyst of claim 9 , wherein the electrolyte removing layer comprises at least one metal oxide.
11. The supported catalyst of claim 10 , wherein the electrolyte removing layer comprises aluminum oxide, titanium oxide, zirconium oxide, tungsten oxide, a doped oxide thereof, or a mixture thereof.
12. The supported catalyst of claim 10 , wherein the electrolyte removing layer has a surface area of at least about 50 m 2 /g.
13. The supported catalyst of claim 1 , wherein the supported catalyst is free of silicate.
14. A molten carbonate fuel cell comprising the supported catalyst of claim 1 as a direct internal reforming catalyst.
15. The molten carbonate fuel cell of claim 14 , wherein the direct internal reforming catalyst retains at least about 60% of its initial catalytic activity after 500 hours of operation.