Deactivation of SOFC anode substrate for direct internal reforming

1. A SOFC, comprising:

a cathode electrode;

a solid oxide electrolyte;

an anode electrode;

a hydrocarbon fuel inlet; and

further comprising at least one of:

(a) porous gradient mask located over at least a portion of the anode electrode at least adjacent to the hydrocarbon fuel inlet;

(b) a mask located over a first portion of the anode electrode adjacent to the hydrocarbon fuel inlet such that a leading edge of a second portion of the anode electrode exposed by the mask forms a non-straight line facing the hydrocarbon fuel inlet;

(c) the anode electrode comprising a smaller thickness in a first portion closer to the hydrocarbon fuel inlet than in a second portion farther away from the hydrocarbon fuel inlet; or

(d) a fuel stream diversion plate located in an anode flow cavity, wherein the fuel stream diversion plate comprises a corrugated plate defining a plurality of openings.

2. The SOFC of claim 1 which comprises two or more of elements (a) to (d).

3. The SOFC of claim 1 comprising a porous gradient mask located over at least a portion of the anode electrode adjacent to the hydrocarbon fuel inlet, wherein a thickness of the gradient mask decreases in a direction from the hydrocarbon fuel inlet to a fuel outlet.

4. The SOFC of claim 3 , wherein the gradient mask extends less than 50% of a length of the anode electrode as measured from the hydrocarbon fuel inlet toward the fuel outlet.

5. The SOFC of claim 1 comprising a mask located over a first portion of the anode electrode adjacent to the hydrocarbon fuel inlet such that a leading edge of a second portion of the anode electrode exposed by the mask forms a non-straight line facing the hydrocarbon fuel inlet.

6. The SOFC of claim 1 , wherein the anode electrode has a smaller thickness in a first portion closer to the hydrocarbon fuel inlet than in a second portion farther away from the hydrocarbon fuel inlet.

7. The SOFC of claim 1 , comprising a fuel stream diversion plate located in an anode flow cavity, wherein the fuel stream diversion plate comprises a corrugated plate defining a plurality of openings.

8. The SOFC of claim 7 , wherein the plurality of openings are located throughout the fuel diversion plate except in a portion adjacent to the hydrocarbon fuel inlet.

9. The SOFC of claim 7 , wherein the plurality of openings are spaced farther apart from each other in a first portion of the fuel diversion plate adjacent to the hydrocarbon fuel inlet than in a second portion of the fuel diversion plate adjacent to a fuel outlet.

10. The SOFC of claim 7 , wherein the plurality of openings have a smaller size in a first portion of the fuel diversion plate adjacent to the hydrocarbon fuel inlet than in a second portion of the fuel diversion plate adjacent to a fuel outlet.

11. A method of operating a SOFC which comprises a cathode electrode, a solid oxide electrolyte, an anode electrode, and a hydrocarbon fuel inlet, said method comprising the steps of:

(a) providing a hydrocarbon fuel to the anode electrode and reforming the hydrocarbon fuel at the anode electrode,

(b) dispersing the hydrocarbon fuel over the anode electrode with a:

i. porous gradient mask located over at least a portion of the anode electrode at least adjacent to the hydrocarbon fuel inlet;

ii. a mask located over a first portion of the anode electrode adjacent to the hydrocarbon fuel inlet such that a leading edge of a second portion of the anode electrode exposed by the mask forms a non-straight line facing the hydrocarbon fuel inlet;

iii. the anode electrode comprising a smaller thickness in a first portion closer to the hydrocarbon fuel inlet than in a second portion farther away from the hydrocarbon fuel inlet; or

iv. a fuel stream diversion plate located in an anode flow cavity, wherein the fuel stream diversion plate comprises a corrugated plate defining a plurality of openings.