水热法制备BaTiO3粉体

水热法制备的陶瓷粉体结晶度高，团聚少，烧结活性闹，得到了越来越广泛的重视。本文报道了水热法制备ＢａＴｉＯ３粉体的研究结果，给出ＢａＴｉＯ３粉体晶粒组成、粒度和结晶形貌与反应温度、前驱物形式以及Ｂａ、Ｔｉ摩尔比之间的关系，选择较高的反应温度，使用强碱性溶液以及较高ｍ（Ｂａ）．ｍ（Ｔｉ）比的前驱物，有利于钙钛矿型ＢａＴｉＯ３晶粒的形成。采用新制的Ｔｉ（ＯＨ）４胶体为前驱物，在Ｂａ（ＯＨ）２水溶液水热反

Hydrothermal Synthesis of BaTiO_3 Fine Powders

Much and much attention was given to the hydrothermal synthesis of ceramic powders, due to the well crystallized, weakly agglomerated ceramic powders with well sinterability can be prepared by this technique. The results of hydrothermal preparation of BaTiO3 fine powders were reported. The chemical form of the precursors on the phase composition, the size and the morphology of the products were found out. The higher the temperature, the higher the acidity and the greater the molar ratio of Ba/Ti in the precursor, the easier the formation of the perovskite type BaTiO3 crystallite. Hydrothermal reaction of the newly prepared Ti(OH)4 gel with the Ba(OH)2 solution produced highly crystallized, well dispersed perovskite type BaTiO3 crystallites with very fine(<100nm) particles. The newly prepared Ti(OH)4 gel turnes out to be a suitable precursor for the hydrothermal preparation of BaTiO3 fine powder. X-ray diffraction (XRD) of the hydrothermal BaTiO3 powders reveals a simple cubic perovskite structure. Above all, the lattice constant (a) decreases with the increase of the reaction temperature. These abnormal crystallographic features are assumed to result from lattice defects, due to the OH- incorporated in the perovskite lattice.