Production of hydrogen and oxygen by water splitting using laser induced photo-catalysis over Fe2O3

Laser induced photocatalytic splitting of water into hydrogen and oxygen has been studied. The activity of pure Fe2O3 catalyst and various electron captureg agents, such as Fe3+, Ag+, Al+3, and Li+, in the water splitting process under the irradiation of a strong laser beam at 355 nm has been investigated for the first time. The amounts of hydrogen and oxygen produced within a short span of time were quite substantial and the photonic efficiency achieved using pure Fe2O3 was much higher than the reported conventional lamp based photocatalysis techniques. The yields of hydrogen and oxygen produced were affected considerably by the addition of electron capture agents. The highest electron capture activity was observed for Fe3+. In addition to monitoring the activity of the Fe2O3 catalyst for hydrogen and oxygen production, pH changes in the colloidal suspension during the photocatalytic process were also investigated. The parametric dependence of the yield as a function of laser beam intensity, irradiation (exposure) time, and concentration of the active material was carefully studied. (C) 2004 Elsevier B.V. All rights reserved.