Magnetic photocatalysts containing TiO2 nanocrystals: Morphology effect on photocatalytic activity
Magnetic photocatalysts containing TiO2 nanocrystals: Morphology effect on photocatalytic activity
复制标题
含有 TiO2 纳米晶体的磁性光催化剂：形态对光催化活性的影响
DOI：
10.1557/jmr.2013.233
复制
发表时间：
2014-01-14
影响因子：
2.7
通讯作者：
Liang, Xin
中科院分区：
文献类型：
--
作者：
Liu, Huan;He, Yeheng;Liang, Xin
通过简单的直浸法制备了含有10 nm以下两种不同形态（纳米颗粒和纳米棒）的TiO2纳米晶体Fe3O4@TiO2磁性光催化剂。一系列有机污染物降解的对比实验表明，Fe3O4@TiO2纳米棒比Fe3O4@TiO2纳米棒具有更好的活性和更快的降解速度。结合高分辨率透射电镜的研究，给出了晶体模型，分析了TiO2纳米晶的形貌对其光催化有机降解活性的影响。具有（100）个以上晶面的TiO2纳米棒具有较高的表面能和相对较高的Ti原子密度，其活性高于TiO2纳米颗粒。此外，Fe3O4@TiO2纳米棒和Fe3O4@TiO2纳米颗粒都表现出比若干比较Fe3O4@TiO2样品更好的光催化活性，这是由于TiO2纳米棒和纳米颗粒的微小尺寸产生了强烈的尺寸效应。这些磁性光催化剂在分离和回收利用方面也具有优势。
Fe3O4@TiO2 magnetic photocatalysts containing sub-10-nm TiO2 nanocrystals with two different morphologies (nanoparticles and nanorods) were prepared via a facile straight dipping process. A series of comparative experiments on organic pollutant degradation demonstrated that Fe3O4@TiO2 nanorods show superior activity and faster degradation rates than Fe3O4@TiO2 nanoparticles. Combined with the study of high resolution transmission electron microscopy, crystal models are given to analyze the morphology effect of TiO2 nanocrystals on their photocatalytic activities for organic degradation. TiO2 nanorods with more (100) crystal planes, which have relatively higher surface energy and relative higher density of Ti atoms, showed a higher activity than that of TiO2 nanoparticles. Furthermore, both Fe3O4@TiO2 nanorods and Fe3O4@TiO2 nanoparticles show better photocatalytic activities than several comparison Fe3O4@TiO2 samples due to the strong size effect arising from the tiny size of TiO2 nanorods and nanoparticles. These magnetic photocatalysts also show advantages in separation and recycling utilization.