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用水热法制备掺镁钛酸钡(Ba1-xMgxTiO3(x=0,0.10,0.20,0.30,0.40),BMT)纳米粉体。运用X射线衍射仪(XRD)、场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、紫外可见漫反射光谱技术(DRS)等手段对样品进行了表征,并在可见光照射下于溶液中考察了其光催化降解甲基橙反应活性。结果表明,通过控制氢氧根浓度可以得到不同形貌的纳米粉体。基于不同条件下制备的样品的微结构分析,提出了这些不同形貌的形成机制。制备出的BMT材料的带隙能约为2.61 eV。光催化反应结果表明BMT的光催化活性比掺氮TiO2高得多。OH-浓度为8 mol·L-1时制备的BMT纳米棒光催化效率最高,经可见光照射360 min,浓度为0.01 mmol·L-1甲基橙溶液的降解率可达到93.0%,且循环使用4次后,其光催化活性并没有明显降低,表明BMT是一种稳定有效的可见光催化剂.
Preparation of barium magnesium titanate (Ba1-xMgxTiO3 (x = 0,0.10,0.20,0.30,0.40), BMT) nanopowder was prepared by hydrothermal method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-Vis diffuse reflectance spectroscopy (DRS) The photocatalytic degradation of methyl orange was investigated. The results show that nano-powders with different morphologies can be obtained by controlling the concentration of hydroxide. Based on the microstructure analysis of the samples prepared under different conditions, the formation mechanism of these different morphologies was proposed. The prepared BMT material has a bandgap energy of about 2.61 eV. The photocatalytic reaction results show that the photocatalytic activity of BMT is much higher than that of nitrogen-doped TiO2. The photocatalytic efficiency of BMT nanorods prepared with OH- concentration of 8 mol·L-1 was the highest, and the degradation rate of methyl orange solution with concentration of 0.01 mmol·L-1 was up to 93.0% after 360 min exposure to visible light. After 4 times, its photocatalytic activity was not significantly reduced, indicating that BMT is a stable and effective visible light catalyst.