| Summary: | 碩士 === 國立雲林科技大學 === 環境與安全衛生工程系 === 105 === The titanium dioxide and bismuth oxide with different molar ratio were prepared composite photocatalyst in this study. The as-prepared I/Bi2O3/TiO2 catalysts were measured the crystalline phase, absorbance and functional group of catalysts. Photocatalytic activities of photocatalysts were evaluated by degrading aqueous bisphenol A (BPA) under different artificial light (UV and simulated sunlight) with continuous-flow system. In UV-Visible results, modified photocatalyst reduced the catalyst energy gap existing the second absorption wavelength in visible zone, it is beneficial to improve the use of photocatalysts for visible light. The photocatalytic activity iodine and bismuth oxide doped titanium dioxide respectively added 2.0 mole% and 1.0 mole% (2.0IBT) was illustrated and discussed in comparison with pure TiO2. Using the 2.0IBT, the degradation effect of aqueous BPA was from 60.7 to 88.8% under UV light, and from 76.1 to 100% under simulated sunlight lighting 22 minutes. The recycling test maintained effectively after ten repeated experiments, which indicate the stability and reusability. The biotoxicity using Microtox analysis was indicated that aqueous BPA of the acute toxic (TUa) was decreased obviously, to achieve the effect of reducing the environmental impact of pollutants. Electron paramagnetic resonance (EPR) measurements reveal remarkable differences on the type of radicals produced after UV and simulated sunlight light illumination of TiO2 and 2.0IBT photocatalysts. The results showed that the presence of iodine and bismuth oxide doped TiO2 played a predominant role in inhibiting the recombination of the photogenerated electrons and holes. All above-mentioned factors cooperated to result in the enhanced photoactivity of the I/Bi2O3/TiO2.
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