铁掺杂TiO 2纳米粉体的制备、表征及光催化性能研究

摘要

Fe3+-doped TiO2 nano-particles were prepared by a hydrothermal process and characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy(FT-IR). Photocatalytic activity of the catalyst was investigated with methyl red as degradation substance under visible-light. The XRD results indicate that as-prepared titanium dioxide crystals possess anatase structure, which has the best photocatalytic activity in the three kinds of crystal types. The results of FT-IR show that there are a lot of—OH groups in as-prepared TiO2 nano-particles; The photo-catalysis results show that Fe doping can significantly improve the photo-catalytic activity of TiO2, the sample powder with 1.4% (mole fraction) Fe3+ has the best ability of photo-degradation. In comparison with pure TiO2 nanoparticles,the photo-degradation efficiency could be improved to 33.66% after reaction for 2 h. The best degradation rate of methyl red is 76.38% under follow optimal conditions: methyl red’s initial concentration is 2 mg/L (pH=6), iron-doping amount is 1.4 % (mole fraction), catalyst dosage is 0.8 g/L, and irradiated by 95 W filament lamp for 2 h at room temperature.%采用水热法制备了铁掺杂的TiO 2纳米粉体，通过X射线衍射(XRD)和傅立叶交换红外光谱(FT-IR)对样品进行表征。以甲基红模拟废水的降解率考察自制的铁掺杂TiO 2纳米粉体的光催化活性。XRD结果说明，产物为锐钛型TiO 2，在其三种晶型中光催化性能最好；FT-IR结果表明：所制的TiO 2结构中存在大量的—OH，预计它有较高的光催化活性；光催化性能实验结果显示：铁掺杂显著提高纳米TiO 2光催化活性，当Fe的掺杂量为摩尔分数1.4%时，其光催化活性最好，与纯TiO2相比，光照2 h后甲基红的光催化降解率提高了33.66%；在最佳条件下（甲基红初始浓度为2 mg/L、pH值为6、掺Fe3+量为摩尔分数1.4%、催化剂用量为0.8 g/L，可见光源为95 W白炽灯、光照为2 h），它对甲基红的降解率达到76.38%。