摘要
本文研究了水热条件下制备的BaTiO3晶粒中OH-缺陷的形成。实验表明,随着溶液中的钡钛摩尔比增大,产物中的OH-缺陷减少,四方相BaTiO3的含量增多。从结晶化学的角度剖析了BaTiO3与锐钛矿结构的相似性,两种晶粒中的Ti—O6八面体的结晶方位一致,其顶角分别指向晶轴a,b和c,因此锐钛矿的生长基元可以往BaTiO3晶粒上配向生长,在结构失配处即可形成缺陷,在缺陷部分TiO6八面体自由端处保留了OH-结构,这是形成晶粒中OH-缺陷的主要原因。
The formation of OH - defect in BaTiO 3 crystallite has been studied.It has been found that OH - defect concentration decrease and content of tetragonal BaTiO 3 in product increase with increasing of Ba /Ti molar ratio in solution.The structure similarity between BaTiO 3 and anatase has been discussed on the crystal chemistry viewpoint.The crystallization orientation of TiO 6 octahedra in these two crystals are both point to the crystal axis a,b and c .Thus the growth units of anatase can epitaxially grow on BaTiO 3 crystallites.The defects are formed when the structure mismatch ocurred,the defects are the free end of TiO 6 octahedron,i.e.OH -.The structure mismatch is the major cause for the formation of OH - defects in the crystallites.
出处
《人工晶体学报》
EI
CAS
CSCD
1996年第3期192-197,共6页
Journal of Synthetic Crystals
关键词
晶粒
水热条件
氧化钛钡
晶体缺陷
BaTO 3 crystallite
hydrothermal condition
OH - defect
growth units