Ba_1-xSr_xTiO₃纳米粉体的水热法制备及其在光催化降解染料中的应用

Hydrothermal Preparation of Ba_1-xSr_xTiO₃ Nanopowder and Its Application in Photocatalytic Degradation of Dye

摘要: 钛酸锶钡Ba_1−xSr_xTiO₃ (BST)由于具有优异的物理化学稳定性和良好的铁电、介电性能广泛应用于电容器、化学传感器等领域。本文通过调控前驱物的浓度和钡锶钛成分比等合成条件，制备了BST纳米级粉体材料。发现通过增加前驱体的浓度可以有效促进Ba_1−xSr_xTiO₃的形成，在低浓度时会生成BaTiO₃或BaTiO₃和SrTiO₃的混合相粉末。在前驱体中增加锶的用量有利于Ba_1−xSr_xTiO₃空心球颗粒的生成，在溶剂中加入乙醇会抑制Ba_1−xSr_xTiO₃空心球的形成。将所制备的Ba_1−xSr_xTiO₃粉体用于光催化降解亚甲基蓝染料溶液，发现Ba_1−xSr_xTiO₃空心球和商用TiO₂粉体P25混合用于光催化降解染料具有协同增效作用。Ba_1−xSr_xTiO₃催化剂的光催化效果优于BaTiO3。

Abstract: Ba_1−xSr_xTiO₃ has excellent physical and chemical stability, as well as good ferroelctric and dielectric properties, and thus it has been widely applied in capacitor, chemical sensor etc. In this work, we prepared BST nanopowders by changing synthesis conditions, such as the concentration of precursors and ratio of Ba, Si, and Ti. It is found that Ba_1−xSr_xTiO₃ inclined to form at higher con-centration of precursors, while at low concentration, BaTiO₃ or mixture of BaTiO₃ and SrTiO₃ was synthesized. Increasing Sr content is good for the preparation of Ba_1−xSr_xTiO₃ hollowsphere, while addition of alcohol as solvent prevented the formation of Ba_1−xSr_xTiO₃ hollowsphere. The Ba_1−xSr_xTiO₃ nanopowder has good photocatalytic activity towards organic dye methyl blue. The synergistic effect between Ba_1−xSr_xTiO₃ hollowsphere and P25 enhanced the photocatalytic activity comparing to single photocatalyst. The photocatalytic activity Ba_1−xSr_xTiO₃ is better than that of BaTiO₃.