Photocatalytic production of hydrogen on Ni/NiO/KNbO_3/CdS nanocomposites using visible light
Abstract
The photocatalytic production of H2 from water splitting was demonstrated on Ni/NiO/KNbO3/CdS nanocomposites using visible light irradiation at wavelengths >400 nm in the presence of isopropanol. The inherent photocatalytic activity of bulk-phase CdS was enhanced by combining Q-sized CdS with KNbO3 and Ni deposited on KNbO3. Enhanced activity is most likely due to effective charge separation of photogenerated electrons and holes in CdS that is achieved by electron injection into the conduction band of KNbO3 and the reduced states of niobium (e.g., Nb(IV) and Nb(III)) are shown to contribute to enhanced reactivity in the KNbO3 composites by mediating effective electron transfer to bound protons. We also observed that the efficient attachment of Q-size CdS and the deposition of nickel on the KNbO3 surface increases H2 production rates. Other factors that influence the rate of H2 production including the nature of the electron donors and the solution pH were also determined. The Ni/NiO/KNbO3/CdS nanocomposite system appears to be a promising candidate for possible practical applications including the production of H2 under visible light.
Additional Information
This journal is © The Royal Society of Chemistry 2008. Received 4th December 2007, Accepted 12th March 2008. First published on the web 2nd April 2008. We are grateful to the Hydrogen Energy Research & Development Center and 21st Century Frontier Research and Development Program of the Ministry of Science and Technology of Korea for research support. This paper is part of a Journal of Materials Chemistry theme issue on hydrogen storage and generation. Guest editor: John Irvine.Attached Files
Published - CHOjmc08.pdf
Files
Additional details
- Alternative title
- Photocatalytic production of hydrogen on Ni/NiO/KNbO3/CdS nanocomposites using visible light
- Eprint ID
- 10944
- Resolver ID
- CaltechAUTHORS:CHOjmc08
- Ministry of Science and Technology (Korea)
- Created
-
2008-06-20Created from EPrint's datestamp field
- Updated
-
2021-11-08Created from EPrint's last_modified field