New photocatalytic systems for hydrogen evolution from water have been reported by using low cost and environmentally-friendly Cu₂ZnSnS₄, Cu₂ZnSnSe₄, and Cu₂ZnSnSe_4−xS_x nanofiber catalysts in the presence of eosin Y as a photosensitizer and a sacrificial reducing agent triethanolamine under visible light irradiation. The rate of hydrogen evolution with Cu₂ZnSnS₄ is greater than those with Cu₂ZnSnSe₄ and Cu₂ZnSnSe_4−xS_x, producing hydrogen at 1428 μmol g⁻¹ h⁻¹, 833 μmol g⁻¹ h⁻¹ and 739 μmol g⁻¹ h⁻¹, respectively.