Solar-powered production of molecular hydrogen from water

Abstract

Electrochemical water splitting powered by conventional electricity or photovoltaic arrays produces molecular hydrogen at the cathode, while organic compound oxidation under mild conditions takes place at the anode in competition with the production of oxygen. An electrolytic cell, which is based on the coupling of bismuth-doped titanium dioxide anodes (BiOx-TiO2) With stainless steel (SS) cathodes, is characterized in terms of hydrogen production efficiency and organic compound degradation. In the solar-powered photovoltaic (PV)-electrochemical system, the production of molecular oxygen at the anode is suppressed by the simultaneous oxidation and mineralization of organic compounds dissolved in water. In addition, the anodic oxidation of organic substrates has a synergistic effect on hydrogen production at the cathode that results in a 53% increase in the energy efficiency for H-2 generation at circum-neutral PH in the presence of dilute electrolyte solutions.