A novel membrane reactor for separating hydrogen and oxygen in photocatalytic water splitting
Journal
Journal of Membrane Science
Journal Volume
382
Journal Issue
1-2
Pages
291-299
Date Issued
2011
Author(s)
Abstract
The Z-scheme of water splitting is comprised of H2-photocatalyst and O2-photocatalyst with aid of electron transfer mediator to produce hydrogen and oxygen, respectively. A twin reactor, which divided H2-photocatalyst and O2-photocatalyst in two compartments using a membrane, can separate H2 and O2 thus preventing backward reaction. Pt/SrTiO3:Rh and BiVO4 were used as the H2-photocatalyst and the O2-photocatalyst, respectively. The diffusion of electron mediator, Fe2+/Fe3+, through Nafion membrane was investigated. The transfer rate of mediator ions was remarkably larger than the photoreaction rate, indicating that membrane did not delay the water-splitting reaction in the twin reactor. Under the favorable condition, the hydrogen generation rate reached 0.65μmol/gh and matched the H2/O2stoichiometric ratio of water splitting. We found that the generation of H2in the twin-reactor system was the rate-limiting step of the water-splitting reaction. By using the twin reactor, the deactivation of Pt/SrTiO3:Rh could be minimized due to the suppression of Fe(OH)3formation on the photocatalyst surface. © 2011 Elsevier B.V.
Subjects
Hydrogen; Membrane reactor; Photocatalysis; Photocatalytic water splitting; Renewable energy
SDGs
Other Subjects
Backward reactions; Electron mediator; Electron transfer mediators; Favorable conditions; Hydrogen generations; Membrane reactor; Nafion membrane; Photocatalytic water splitting; Photoreactions; Rate-limiting steps; Renewable energies; Stoichiometric ratio; Transfer rates; Water splitting; Bioreactors; Hydrogen; Hydrogen production; Oxygen; Photocatalysis; Rhodium; Membranes; bismuth; bismuth vanadate; ferric ion; ferrous ion; hydrogen; iron oxide; oxygen; platinum; rhodium; strontium; strontium titanate; unclassified drug; vanadium; water; article; catalyst; chemical reaction; diffusion; electrochemistry; electron transport; membrane reactor; molecular weight; photocatalysis; photocatalyst; photocatalytic water splitting; photoreactivity; priority journal; scanning electron microscopy; separation technique; stoichiometry; transmission electron microscopy; X ray diffraction; X ray photoelectron spectroscopy
Type
journal article