Application Of Titanium Dioxide Nanotube Array In The Trace Analysis Of Environmental Pollutants

Recently, highly ordered TiO₂nanotube array was introduced as a new kind of TiO₂materials. Incontrast, it has much larger specific surface area than that of TiO₂nanotube powders. Except these, TiO₂nanotube is connected with the substrate directly and tightly, and not easy to be desquamated. Because ofthe highly ordered structure and non-agglomeration, it is very stable and easy to realize cycled applicationof TiO₂nanotube array. So TiO₂nanotube array absorbed much more attention. However, there are veryfew reports on the application of TiO₂nanotube array in environmental analytical field. Due to their specialphysical and chemical properties, TiO₂nanotube array should play an important role in environmental field,especially in preconcentration and detection of environmental pollutants, and have a great prospect.In this thesis, on the basis of a large number of literatures, TiO₂nanotube array was investigated fordevelopment of micro-solid phase equilibrium extraction as adsorbents, and BPA,4-OP,4-NP,organochlorine pesticides were used as the model analytes. This thesis could be divided into four parts.In the first part, a review was presented on the the research progress of TiO₂nanotube materials andthe preparation and application of TiO₂nanotube array.In the second part, the potential of TiO₂nanotube array as absorbent for environmental endocrinedisruptors was investigated. The experimental results show that BPA,4-OP,4-NP can be quantitativelyabsorbed on TiO₂nanotube array sheet. This method has been applied to determine BPA,4-OP,4-NP inseveral environmental water samples. The detection limits of the developed method were0.022μg L^-1,0.049μg L^-1,0.0093μg L^-1respectively. The spiked recoveries from real environmental water sampleswere in the range of74.8–106.2.6%.The potential of TiO₂nanotube array as absorbent for organochlorine pesticides was investigated in thethird part. The experimental results show that organochlorine pesticides can be quantitatively absorbed onTiO₂nanotube array sheet. This method has been applied to determine heptachlor, heptachlor-epoxide,α-endosulfan, dieldrin, endrin, β-endosulfan, endosulfan sulfate, methoxychlor in several environmentalwater samples. The detection limits and the linear ranges of the developed method were in the range of 0.018-0.19μg L^-1and0.05-100μg L^-1, respectively. The spiked recoveries from real environmental watersamples were in the range of75.1-107.0%.In the last part, the potential of TiO₂nanotube array as absorbent for benzoylurea insecticides wasinvestigated. The experimental results show that benzoylurea insecticides can be quantitatively absorbed onTiO₂nanotube array sheet. This method has been applied to determine benzoylurea insecticides in severalenvironmental water samples. The detection limits and the linear ranges of the developed method were inthe range of0.026-0.082μg L^-1and0.1-40μg L^-1, respectively. The spiked recoveries from realenvironmental water samples were in the range of76.5-102.4%.