Hydrogen generating material and method for producing the same, and method for producing hydrogen

1. A hydrogen generating material comprising:

at least one metal material selected from the group consisting of aluminum and aluminum alloy,

wherein the metal material has a surface film that includes a metal phase containing aluminum in a metallic state and an inactive phase containing an oxide or hydroxide of aluminum, and

wherein the surface film includes a laminated portion in which a layer of the metal phase and a layer of the inactive phase are stacked alternately.

2. The hydrogen generating material according to claim 1 , wherein at least two layers of the metal phase and at least two layers of the inactive phase are stacked in the laminated portion.

3. The hydrogen generating material according to claim 1 , wherein the laminated portion has a thickness of 2 μm or less.

4. The hydrogen generating material according to claim 1 , wherein the surface film has pores.

5. The hydrogen generating material according to claim 1 , wherein the metal material includes particles with a particle size of 60 μm or less in a proportion of 80 vol % or more.

6. The hydrogen generating material according to claim 1 , wherein the metal material has an average particle size of 30 μm or less.

7. The hydrogen generating material according to claim 1 , wherein the metal material includes 60 mass % or more of aluminum in the metallic state.

8. The hydrogen generating material according to claim 1 , further comprising a heat generating material that generates heat by reacting with water.

9. The hydrogen generating material according to claim 1 , further comprising at least one additive selected from the group consisting of a hydrophilic oxide, carbon, and a water absorbing polymer.

10. A method for producing a hydrogen generating material comprising at least one metal material selected from the group consisting of aluminum and aluminum alloy,

wherein the metal material has a surface film that includes a metal phase containing aluminum in a metallic state and an inactive phase containing an oxide or hydroxide of aluminum, and

wherein the surface film includes a laminated portion in which a layer of the metal phase and a layer of the inactive phase are stacked alternately,

the method comprising:

pulverizing aluminum or aluminum alloy in a liquid containing water and an organic solvent.

11. The method for producing a hydrogen generating material according to claim 10 , wherein a content of water in the liquid is 0.02 to 2 parts by mass with respect to 1 part by mass of aluminum or aluminum alloy.

12. The method for producing a hydrogen generating material according to claim 10 , wherein a content of water in the liquid is 0.1 to 1 parts by mass with respect to 1 part by mass of aluminum or aluminum alloy.

13. The method for producing a hydrogen generating material according to claim 10 , wherein the organic solvent includes toluene.

14. The method for producing a hydrogen generating material according to claim 10 , further comprising adding a heat generating material that generates heat by reacting with water to the pulverized aluminum or aluminum alloy.

15. The method for producing a hydrogen generating material according to claim 10 , wherein the surface film has pores.

16. A method for producing hydrogen comprising:

producing hydrogen by a reaction between the hydrogen generating material according to claim 1 and water.

17. The method for producing hydrogen according to claim 16 , further comprising heating the hydrogen generating material and the water.

18. The method for producing a hydrogen generating material according to claim 10 , wherein a content of the organic solvent in the liquid is 5 parts by mass or more with respect to 1 part by mass of water.