Abstract: With a method producing hydrogen by making iron or iron oxide contact water, water vapor, or a gas including water vapor, a hydrogen generating medium, which has a high hydrogen generation reaction rate and is resistant to a repetition of oxidation-reduction without degrading its activity, is provided by adding a different metal (such as Ti, Zr, V, Nb, Cr, Mo, Al, Ga, Mg, Sc, Ni, Cu, etc.) other than the iron to the iron or the iron oxide.

Abstract: Provided is a method of and an apparatus for decomposing hydrogen. The method includes the steps of introducing hydrocarbons into a reaction vessel in a closed-loop system, at least partially decomposing the hydrocarbons into hydrogen by heating the hydrocarbons in the reaction vessel in the presence of a catalyst, introducing the hydrogen into a cassette with metal oxide contained therein, reducing the metal oxide in the cassette to metal or metal oxide having a lower valence by at least partially reacting the metal oxide with the hydrogen to form water, and returning unreacted hydrogen to the reaction vessel. Also provided is a method for producing hydrogen for an apparatus in need thereof.