水热法制备高结晶度分散性铌酸钾钠粉体

Preparationof Potassium-Sodium Niobate Powders with High Dispersity and Crystallinity by Hydrothermal Synthesis

采用水热法制得纯钙钛矿相的(K_(0.5)Na_(0.5)NbO_3(KNN)超细粉体,并探索超声分散和水热反应时间对该无铅压电陶瓷KNN粉体颗粒大小以及颗粒相结构的影响。通过X射线衍射(XRD)和扫描电镜(SEM)对所得铌酸钾钠粉体的结构、颗粒大小进行了测试与表征。结果表明,经过750℃保温1h得到的粉体粒径细小,呈现纯钙钛矿结构;适当延长水热反应时间有利于结晶度的提高;超声处理有利于得到高分散性的粉体。

Pure perovskite phase（K_（0.5）Na_（0.5））NbO_3（KNN） ultra-fine powder was prepared by hydrothermal method, and the effect of ultrasonic dispersion and the hydrothermal reaction time on the size and the phase structure of the KNN powders were investigated. The structure of the potassium-sodium niobate powders were analyzed by x-ray diffraction analysis（XRD） and the powder size was measured by scanning electron microscopy（SEM）. The results showed that the KNN powders calcined at 750 ℃for 1 h were pure perovskite structure and the particle size was small. The appropriate extension of the hydrothermal reaction time is conducive to increase the crystallinity, and ultrasonic dispersion is conducive to obtain a highly dispersed fine powder.