| abstract |
The method for producing hydrogen gas comprises a light irradiation step of generating a gas containing hydrogen by irradiating the surface of a metal material immersed in water with light, the metal material containing iron, and in the light spectrum, The wavelength having the maximum intensity is 360 nm or more and less than 620 nm, and at least one of iron oxide and iron hydroxide is formed on the surface as the gas is generated. |