2007 Fiscal Year Final Research Report Summary
Photocatalytic degradation of volatile chlorinated organic compounds on CuffiO_2 films prepared by size-controlled Cu deposition
| Project/Area Number |
18550180
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Inorganic industrial materials
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| Research Institution | Yamaguchi University |
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Principal Investigator |
YAMAZAKI Suzuko Yamaguchi University, Graduate School of Science and Engineering, Professor (80202240)
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| Project Period (FY) |
2006 – 2007
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| Keywords | photocatalyst / film / metal-loaded TiO_2 / materials for environmental remediation |
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| Research Abstract |
Cu-deposited TiO_2 (Cu/TiO_2) films were prepared by photoreduction of Cu(II) in the presence of sodium formate. With the initial Cu(II) concentrations less than 50 mg L 1, the transmittance of the films decreased with an increase in the irradiation time. After the irradiation for 6 hrs, the scanning electron microscopy (SEM) indicated that the most of the Cu particles on the films were 0.51±0.04 μm. On the other hand, when irradiation was conducted in 100 or 150 mg L^<-1> Cu(II) solution, induction periods were observed before the transmittance decreased. The SEM images of the films indicated that Cu particles of 2.6±0.5 μm were deposited isolatedly with much open space in the induction periods. These facts proposed two methods to fabricate the Cu/TiO_2 films. The Cu amounts loaded on the film can be verified by changing the initial Cu(II) concentration less than 50 mg L^<-1> (method A), or changing the irradiation time within the induction period under the Cu(II) concentration above 100 mg L^<-1> (method B). The photocatalytic activities of the Cu/TiO_2 films prepared by both methods followed by calcination at 500℃ were compared in the degradation of methylene blue in aqueous solutions. The films prepared by method B showed a higher photocatalytic activity than a pure TiO_2 under no purging with air. This finding is attributable to higher transmittance of the films and function of the Cu particles as the electron trap which leads to suppression of the recombination between holes and electrons. Photocatalytic degradation of trichloroethylene (TCE) in the gas phase was also performed on the Cu/TiO_2 films prepared by method B. However, the TCE conversion decreased drastically with an increase in the irradiation time. This fact suggests that the accumulation of the by-products significantly affected the performance of the Cu/TiO_2 films.
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Research Products
(4 results)
