纳米网状结构钛酸锶钡的制备及其催化性能研究（英文）

Fabrication of Barium Strontium Titanate Nanophotocatalysts with Gridding Structures and Their Photocatalytic Activities

采用溶胶–凝胶法在不同pH值条件下制备了纳米钛酸锶钡(BST)粉体。在pH值为4和2.4条件下合成的BST粉体都是单相并结晶良好。透射电镜结果显示,BST纳米粉体颗粒尺寸大约为100nm,当pH值为4时BST纳米颗粒开始通过相互连接形成纳米网状结构。经光催化降解罗丹明B研究发现,在pH值为4条件下制备的纳米BST粉体表现出更高的光催化活性。这可能是因为在pH值为4时纳米网状结构的BST形成提高了光生载流子的迁移率,从而提高了纳米BST在有机物降解过程中光催化效率。

Ba0.7Sr0.3TiO3 （BST） nanocatalysts were prepared by a Sol-Gel method at pH of 2.4 and 4, respectively, both of which were presented as tetragonal phase. TEM images indicated that the BST sample obtained at pH = 2.4 was nanoparticles with an average size of about 100 nm, while that obtained at pH = 4 was gridding structures composed of nanocubes with a mean size of 100 nm. The photocatalytic behavior of BST in the degradation of Rhodamine B （RhB） was investigated. It was found that the BST catalysts with gridding structures showed much better photocatalytic performance than the BST nanoparticles. This could be attributed to the fact that the photo-generated carriers can migrate easily through the gridding-structured BST sample, which would enhance the photocatalytic activity during the degradation process. It was also found that both BST photocatalysts in this work showed good catalytic stability.