水热法制备的BaTiO3微晶粒的特性

本文报道了对水热法制备的ＢａＴｉＯ３纳米微粒性质和缺陷研究的结果．水热法制备的ＢａＴｉＯ３纳米微粒形貌和线度可通过改变前驱物形式和反应条件加以适度调控．在一定的条件下，水热法得到的是在常温下能稳定存在的立方相ＢａＴｉＯ３晶粒．这种“反常”结晶学特性是由于晶粒里含有一定量的Ｏ－Ｈ缺陷和钡离子空位缺陷所造成的．选择适宜的反应条件（如提高反应前驱物钡钛摩尔比等）或采用一定的处理手段（如热处理等），减少或消除这类缺陷，即可消除此“反常”结晶学特性．

Properties of Hydrothermal BaTiO_3 Micro-crystal

The properties and the defects of the hydrothermal BaTiO3 crystallites were studied. It was found that the hydrothermal BaTiO3 crystallites can be somewhat tailor-made by controlling the kind of the precursors used and the reaction conditions. Hydrothermal BaTiO3 crystallites usually reveal a simple cubic perovskite structure at room temperature. Such an abnormal crystallographic feature is attributed to the O-H' defects and the VBa defects in the crystallite. When proper reaction condition (e. g. using the precursors with high barium to titanium molar ratio) is selected or some treatment measures (e. g. thermal treatment ) are taken, these defects can be lightened or healed up and the abnormal crystallographic feature