ZrO_2超细粒子的制备与表征

The Preparation and Characterization of Ultrafine ZrO_2

以共沉淀结合喷雾干燥的方法制备了纳米级的ＹＴＺ粉料（以Ｙ２Ｏ３稳定的ＺｒＯ２），讨论了反应物浓度、碱度、烧结方法、成粒方法、烧结条件等对粉料的影响．热分析和ＸＲＤ（Ｘ－射线衍射）分析显示，当温度从常温升至７００℃，粉料经历了由无定形向四方相、单斜相晶体的转变，相变温度分别是４５０、７００℃．对烧结过程的研究发现，在３００℃处并非为简单的失水过程而是相转变．用ＴＥＭ（透射电子显微镜）观察了粉料团聚体的形貌、尺寸，ＴＥＭ及Ｘ射线线宽法确定晶粒的大小约２０ｎｍ；ＢＥＴ法测得其比表面积最高可达７９．５ｍ２／ｇ．

Nano-sized YSZ (ZrO_2 stabilized by Y_2O_3) powder was prepared by coprecipitation-spry-drying method.The influence of concentrations, basicity and sintering process on YSZ powder was discussed.With DTA and X-Ray spectra,it was found that several phase transformation took place when heated from room temperature to 700℃.Especially at 300℃,the heating effected a phase tramsformation process,rather than a simple dehydration.Several phase transformation prosesses were studied in detail.Particle size,morphology and agglomerated states were observed by TEM.The particle size wasa bout 20 nm with TEM and XRD-LB.A specific surface area of 79.5m^2·g^-1 was measured by BET method.