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چکیده
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Transition metal dopants have been used to decrease the band gap energy of TiO2 for visible light photocatalytic purposes [1]. Fe3+ is a good dopant candidate owing its unique half-filled electronic configuration, which can not only narrow the energy gap through the formation of new intermediate energy levels and but also help the separation of photogenerated electrons and holes [2]. Electrospun nanofibers have attracted much interest as a new form of photocatalyst due to their excellent properties, including a large surface to volume ratio, high porosity and interconnected pores [3]. Therefore, in this work, Fe-doped TiO2 nanofibers have been fabricated using a sol–gel method and electrospinning technique with different Fe3+ contents. The effect of the Fe3+ concentration on the photocatalytic properties of these nanofibers have been investigated through the study of the degradation of a pollutant model (rhodamine B) using a visible light source. The experimental results demonstrate that the Fe-doped TiO2 nanofibers exhibit significantly enhanced activity toward the rhodamine B degradation under visible light illumination in comparison with commercial TiO2 powder(P-25) and undoped TiO2 nanofibers. The maximum degradation which was observed for rhodamine B is 71% in 4 hours when the Fe3+ molar concentration was 1mol%. While this value was 51% and 53% for P-25 and undoped TiO2 nanofibers, respectively.
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