板钛矿和锐钛矿TiO_2对水热合成Bi_4Ti_3O_(12)微结构的影响

The influences of brookite and anatase TiO_2 on the microstructure of Bi_4Ti_3O_(12) synthesized by a hydrothermal method

分别以板钛矿和锐钛矿型的TiO2为先驱物水热合成钛酸铋亚微米棒.由X射线衍射、选区电子衍射以及Raman光谱的测量结果可知,合成的产品为Bi4Ti3O12.源自板钛矿和锐钛矿的Bi4Ti3O12,其结构表现出明显的差异.在同样的条件下,Bi插入锐钛矿TiO2的量多于其插入板钛矿TiO2的量,从而导致部分X射线衍射峰向高角度方向稍微移动.保留下来的短Ti—O键限制了b-Bi4Ti3O12亚微米棒沿[010]方向生长,使得b-Bi4Ti3O12亚微米棒长度不均.

Bismuth titanate submicron rods are synthesized by hydrothermal method using anatase and brookite nanocrystallites, respectively, as precursors. The results of XRD, SAED and Raman spetra indicate that two samples can be indexed to the same Bi4Ti3O12 phase. The corresponding products, a- and b Bi4Ti3O12 submicron-rods, have distinct differences in structure. The cause for the shift of diffraction peaks is that the amount of Bi intercalated into anatase TiO2 is larger than that into brookite TiO2 under the same conditions. The multiple types of reserved short Ti-O bonds in b-Bi4Ti3O12 confine the growth of submicron-rods along the [010] orientation, which makes b Bi1Ti3O12 submicron-rods uneven.