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Abstract：
In this study, the optimal microwave-assisted sol-gel synthesis parameters for achieving TiO2 nanoparticles with the highest specific surface area and photocatalytic activity were determined. Titanium isopropoxide was used as a precursor to prepare the sol (colloidal solution) of TiO2. Isopropanol was used as a solvent; acetylacetone was used as a complexation moderator; and nitric acid was used as a catalyst. Four samples of titanium dioxide were synthesized from the prepared colloidal solution in a microwave reactor at a temperature of 150 °C for 30 min and at a temperature of 200 °C for 10, 20, and 30 min. The phase composition of the TiO2 samples was determined by X-ray diffraction analysis (XRD) and Fourier-transform infrared spectroscopy (FTIR). Nitrogen adsorption/desorption isotherms were used to determine the specific surface area and pore size distributions using the Brunauer-Emmett-Teller (BET) method. The band-gap energy values of the TiO2 samples were determined by diffuse reflectance spectroscopy (DRS). The distribution of Ti and O in the TiO2 samples was determined by SEM-EDS analysis. The effects of adsorption and photocatalytic activity of the prepared TiO2 samples were evaluated by the degradation of ciprofloxacin (CIP) as an emerging organic pollutant (EOP) under UV-A light (365 nm). The results of the photocatalytic activity of the synthesized TiO2 nanoparticles were compared to the benchmark Degussa P25 TiO2. Kinetic parameters of adsorption and photocatalysis were determined and analyzed. It was found that crystalline TiO2 nanoparticles with the highest specific surface area, the lowest energy band gap, and the highest photocatalytic degradation were the samples synthesized at 200 °C for 10 min. The results indicate that CIP degradation by all TiO2 samples prepared at 200 °C show a synergistic effect of adsorption and photocatalytic degradation in the removal process.
摘要：
在这项研究中,确定了最佳的微波辅助溶胶-凝胶合成参数，以获得具有最高比表面积和光催化活性的TiO2纳米颗粒。使用异丙醇钛作为前体来制备TiO2的溶胶(胶体溶液)。使用异丙醇作为溶剂;使用乙酰丙酮作为络合缓和剂;并且使用硝酸作为催化剂。由制备的胶体溶液在微波反应器中在150°C的温度下30分钟和在200°C的温度下10、20和30分钟合成四个二氧化钛样品。通过X射线衍射分析（XRD）和傅立叶变换红外光谱（FTIR）确定了TiO2样品的相组成。使用Brunauer-Emmett-Teller（BET）方法，使用氮吸附/解吸等温线确定比表面积和孔径分布。TiO2样品的带隙能量值通过漫反射光谱(DRS)测定。通过SEM-EDS分析确定Ti和O在TiO2样品中的分布。通过在UV-A光（365nm）下降解环丙沙星（CIP）作为新兴的有机污染物（EOP）来评估所制备的TiO2样品的吸附和光催化活性的影响。将合成的TiO2纳米颗粒的光催化活性的结果与基准DegussaP25TiO2进行比较。确定并分析了吸附和光催化的动力学参数。发现具有最高比表面积的结晶TiO2纳米颗粒，最低的能带隙，光催化降解最高的是在200°C下合成10分钟的样品。结果表明，在200°C下制备的所有TiO2样品对CIP的降解在去除过程中表现出吸附和光催化降解的协同作用。
