Synthesis And Modification Of Tiohotocatalytic Performance For Tet2nanotubes And Their Pracycline Degradation From Aqueous Solutions

Tetracycline class antibiotics show an important activity towards a variety of microorganisms and thus they are widely used as broad-spectrum antibiotics in human beings,animals and agriculture. When antibiotics released into the environment, antibiotics can affectaquatic organisms, cause bacterial resistance, high toxicity, difficult to treatment, complicatedcomposition. At the same time the negative impact of antibiotics residue in water pose therisk to the health of human, therefore, it is more and more attented by us. So, it’s importantthat to deal with the antibiotic wastewater. TiO2photocatalytic oxidation technology is anew-style environmental pollution control technology, whose virtues are simply equipments,highly treatment efficiency, no toxicity, stability chemical and easily operating conditionproperty, etc. Because it produces highly oxidative hydroxyl free radicals (·OH) that results incomplete mineralization of many non-biodegradable and toxic organics. It also has thepotential to use of solar energy.This paper intends to present our research results on the doping and exchangingmodification of TiO2nanotubes and their photocatalytic performance for tetracyclinedegradation in the light-driven way. The simples were characterized by SEM, TEM, XRD,BET, and the UV-Vis spectroscopy. The results of our investigation and analysis prove that itis possible to fabricate regularly uniform nanotubes through hydrothermal process, and endowthem with homogeneous and multi-walled tubular structures with open ends. The XRD resultsshowed that TiO2powders were completely transformed to TiO2nanotubes, and there is noanatase or rutile phase appeared in the obtained materials. In terms of the morphology andstructure, there was not any significantly difference between ion doped TiO2nanotubes andunmodified TiO2nanotubes, little difference between ion exchanged TiO2nanotubes andunmodified TiO2nanotubes. However, the nitrogen adsorption-desorption isotherm tends toreveal a typical IV adsorption isotherm characterized with the features of mesoporousmaterials. When analyzing the absorbency by using the UV–Vis spectroscopy and comparingthe newly developed TiO2nanotubes with the TiO2powder, we can find that, the saidnanotubes can help greatly improve the absorption ability, for the absorption edge can beextended to the visible light region.In addition, starting from our research demands, we have also done an evaluation of thephotocatalytic degradation testing results of the antibiotics by using catalysts we havedeveloped via the visible light and the xenon lamp (K=250–800nm) irradiation. The photocatalytic activities of ion doped and exchanged TiO2nanotubes were evaluated by thephotocatalytic degradation of tetracycline. The photocatalytic behavior of the ion dopednanotubes was much more better than under ion exchanged nanotubes and unmodified TiO2nanotubes, which was of the following order: Co2+doped＞Fe3+doped＞Ni2+doped＞Co2+exchanged＞Fe3+exchanged＞Ni2+exchanged＞unmodified.