INVESTIGATION FOR THE PURPOSE OF IMPROVING THE EFFICIENCY OF UTILIZATION OF SOLAR ENERGY BY THE DECOMPOSITION OF WATER INTO HYDROGEN AND OXYGEN.
Abstract
The sensitized photo-decomposition of water was studied, with the purpose of improving its ef ficiency as a means of solar energy conversion. A number of metallic cations and other materials were tested for sensitizer activity and, of these, only ceric, thallic, ferrous, iodide, and chromous ions do sensitize the reaction; the former two to yield oxygen, the latter three, hydrogen. In no case was the simultaneous pro duction of hydrogen and oxygen observed. Quantum yields were determined, with substantial conver sion of the sensitizer, and found to be of the order of 10 to minus 2; to 10 to minus 4. Initial yields were much higher. With the known sensitizers, this reaction does not utilize a sufficient fraction of the solar spectrum to be practical as a means of solar energy conversion. Ceric ions oxidize water to yield oxygen in the dark at elevated temperatures. The thermal reaction is catalyzed by platinized platinum whereas the photochemical reaction is not. Ap parently the ceric-water reaction proceeds ther mally and photochemically by different mechanisms. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1963
- Accession Number
- AD0413930
Entities
People
- Donald G. Burkhard
- Harumasa Ito
- Hormoz Mahmoud
- Robert S. Kirk
- Ronald E. West