Energy positions of oxide semiconductors and photocatalysis with iron complex oxides

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1006/jssc.1996.0333· OSTI ID:478809

Matsumoto, Yasumichi ^[1]

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1. Kumamoto Univ. (Japan)

Energy position, bandgap, band structure, and their relationships were reviewed for various oxide semiconductors, especially iron oxides, in photoelectrochemistry and photocatalysis, and the photocatalytic reduction of CO{sub 2} on some iron complex oxides was demonstrated. A linear relationship between bandgap and band edge was obtained for almost all the semiconductor oxides. It was pointed out that a bandgap energy higher than about 2.46 eV is necessary for water photolysis without bias voltage. It was found that the energy positions of the band edge can be controlled by the electronegativity of the metal elements constituting the iron complex oxides. The relationship between the band structure and the charge transfer site was also examined. The photocatalytic reduction of CO{sub 2} to CH{sub 2}OH was demonstrated for CaFe{sub 2}O{sub 4} and Fe-Bi-Sr-Pb-O complex oxides. The photocatalytic activity of the latter oxide with a layer structure increased with increased Pb content. The catalytic mechanism was discussed from the point of view of the redox mechanism as well as the energy position of the band edge.

• OSTI ID: 478809
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 2 Vol. 126; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

10 SYNTHETIC FUELS
36 MATERIALS SCIENCE
40 CHEMISTRY
BAND THEORY
BISMUTH OXIDES
CALCIUM OXIDES
CARBON DIOXIDE
CATALYSIS
CATALYTIC EFFECTS
ELECTRONIC STRUCTURE
IRON OXIDES
LEAD OXIDES
PHOTOCHEMICAL REACTIONS
REDUCTION
SEMICONDUCTOR MATERIALS
STRONTIUM OXIDES