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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。
In this paper, the formation of OH-defects in BaTiO3 grains prepared under hydrothermal conditions was studied. Experiments show that, as the molar ratio of barium and titanium in the solution increases, the OH-defects in the product decrease, and the content of tetragonal BaTiO3 increases. The similarities between BaTiO3 and anatase structure are analyzed from the perspective of crystallographic chemistry. The Ti-O6 octahedra in the two kinds of grains have the same crystallographic orientation with the apex angles pointing to the crystal axes a, b and c, respectively. Thus, anatase Can grow on the BaTiO3 grains and form defects in the structure mismatch. The OH- structure is retained at the free end of the defect portion of the TiO6 octahedra, which is the main reason for the formation of OH- defects in the grains .