Study on the photocatalytic degradation of organic pollutants by thin layer TiO2/ITO electrode with ransition metal modification

Autor: Ming-Yi Chang, 張名毅
Rok vydání: 2010
Druh dokumentu: 學位論文 ; thesis
Popis: 98
The object of this study is to modify the TiO2/ITO photocatalytic electrode with vanadium and lanthanum. The V-doped and La-doped TiO2/ITO photocatalytic electrodes were synthesized by sol-gel method and dip-coating method. Both V-TiO2/ITO and La-TiO2/ITO photocatalytic electrodes were characterized by Field emission scanning electron microscope（FE-SEM）, Electron spectroscopy for chemical analysis system（ESCA）, X-ray diffractometer（XRD）and Isoelectric point（pHIEP）. The photocatalytic and photoelectrocatalytic activities were evaluated by the degradation of methylene blue and Acid Yellow 17 under different parameters. As the results of the external analysis of SEM, ESCA and XRD, the particle size of the TiO2/ITO photocatalytic electrode is about 30 nm and mainly Anatase structure for V-TiO2/ITO. The particle size of V-TiO2/ITO photocatalytic electrodes is not uniform with the size range, from 10nm to 100 nm. But La-TiO2/ITO showed particles of regular shapes with smaller size (＜10 nm) compared to the TiO2/ITO, which presented uniform particles of spherical structure and larger size (20 nm). The contents of the Rutile phase increase with the increase of the amount of doped Vanadium and Lanthanum. Vanadium in the photocatalytic electrodes is in the status of V3+, V4+ and V5+, and lanthanum in the photocatalytic electrodes is in the status of La2+, and La 3+ .The 0.30V/Ti photocatalytic electrode has the best ability both on the adsorption and photocatalytsis. Even in the visible light system, the 0.30V/Ti photocatalytic electrode has great photoactivity as same as in the UV light system. The V-doped TiO2/ITO photocatalytic electrodes may convert N-type semiconductor into P-type semiconductor.
Databáze: Networked Digital Library of Theses & Dissertations
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