四方相钛酸钡纳米枝晶阵列的水热合成

采用水热法，在表面活性剂十六烷基三甲基溴化铵(CTAB)和合适的矿化剂NaOH的作用下，得到具有新颖结构的钛酸钡纳米枝晶阵列。X射线衍射(XRD)和拉曼光谱(Raman)结果分析显示该枝晶为四方相，随着时间的延长其结晶性增强、四方相更加明显。利用扫描电子显微镜(SEM)、高分辨透射电子显微镜(HRTEM)和电子衍射(ED)研究了该枝晶的生长特点和生长机理，结果表明该枝晶其各枝均沿着111]方向生长，并且同级枝相互平行形成阵列；在枝晶阵列的外侧部分会有2级子枝长出，中间部位由于空间阻碍没有子枝形成。同时探讨了CTAB和NaOH在枝晶形成过程中的作用机理，以及枝晶产品的介电性能。

Hydrothermal Synthesis of Tetragonal Barium Titanate Nano-Dendrite Arrays

The novel nano-dendrite arrays structure of barium titanate were prepared by hydrotherrnal method with the assistance of the surfactant N-cetyl-N,N,N-trimethy-lammonium bromide (CTAB) and the mineralizer NaOH. The Powder X-ray diffraction (XRD) patterns and Raman spectroscopy results reveal that the dendrites have been crystallized in the tetragonal phase, the crystallization and the tetragonal phase of the products become more significant with the reaction making progress. The growth characteristics and growth mechanism of the dendrite are further evidenced by the scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and electron diffraction (ED) in detail. The branches of the dendrites grow along the 111] orientation. The branches in the same grade parallel to each other and produce the final array structure. The two sub-branches grow on the trunk in the outside part of the dendrite array, while no sub-branch grow on the trunk in the middle of the dendrite array because of spatial effect. The role of CTAB and NaOH is also discussed in the formation process of the dendrites. The dielectric properties of the dendrties sample are signifcantly improved.