Hydrogen generation from artificial sea water in a semiconductor septum electrochemical photovoltaic cell.

Visible light of the solar spectrum is directly converted to stored chemical energy of hydrogen from artificial sea water in a novel electrochemical photovoltaic cell. The principal element of the cell, modeled after the photosynthetic thylakoid membrane, is a semiconductor septum made of polycrystalline n-CdSe thin film deposited on nickel foil, which separates two aqueous solutions. Under short-circuit conditions, vigorous hydrogen evolution was seen at the Ni surface and continued as long as the cell was operated. The novel cell, the concept of which was derived from pigmented bilayer lipid membrane studies, is easy to construct, simple to operate, and appears to be a practical approach to the photochemical conversion and storage of solar energy.