Highly ordered Fe3+/TiO2 nanotube arrays for efficient photocataltyic degradation of nitrobenzene

作者：Zhang, Yiyang; Gu, Di^*; Zhu, Lingyue; Wang, Baohui^*

来源：Applied Surface Science, 2017, 420: 896-904.

DOI：10.1016/j.apsusc.2017.05.213

• Doped TiO2 NTs
• Preparation
• Anodization
• Photocatalysis
• Mechanism

Highly ordered TiO2 nanotube arrays (TiO2 NTs) were prepared through a facile two-step electrochemical anodization, subsequently, active iron ions were introduced into the TiO2 NTs via a direct impregnation method. The XPS results showed that the iron elements existed in TiO2 NTs in the form of Fe3+ ions. Compared with the undoped TiO2 NTs, the absorption edge of Fe3+/TiO2 NTs showed an overt red shift and the photocurrent improved obviously, which indicated that Fe3+/TiO2 had a much higher photocatalytic activity. The optimal doping content was tested to be 0.1 mol/L which could make the photocatalytic activity of TiO2 NTs obviously improves under both visible and ultraviolent light. The prepared samples were adopted as photocatalyst to degrade nitrobenzene (NB). The reaction rate constants k(s) under UV light were in the order k(one-stepTiO2NTs) = 0.00338 < k(two-ste TiO NTs) = 0.00455 < k(Fe3+/TiO NTs) = 0.00736 which showed the superior photocatalysis activity of Fe3+/TiO2 NTs. The final degradation products were probed to be CO2 and H2O, which demonstrated that NB could be completely mineralized to harmless inorganic substance. The mechanism of NB degradation with Fe3+/TiO2 was also discussed and the quenching experiments further confirm that center dot OH, h(+) and center dot O-2(-) are active intermediates in the process of photocatalytic degradation.

• 出版日期2017-10-31
• 单位东北石油大学