采用低温液相法以廉价的TiCl4、SrCl2、CaCl2为原料,以NaOH溶液为沉淀剂一步合成了纳米SrxCa1-xTiO3固溶体粉体.为了提高粉体颗粒结晶度,改善形貌,进行了水热后处理.通过XRD,TEM,FT-IR,TG和ICP等表征手段对所得粉体的物相、形貌、颗粒尺寸及分布、杂质含量、Ca2+与Ti4+摩尔比进行了分析和测试.结果表明,SrxCa1-xTiO3在0.1≤x≤0.9范围形成了固溶体,且随x的增大相结构从斜方相逐渐过渡到立方相.水热处理前粉体结晶度低,形貌不规整,而进行水热处理后粉体中O-H缺陷和CO2-3杂质显著减少,结晶度提高,形貌规整均匀,随着x从0.3增加到0.9,颗粒粒径从230nm减小到65nm(水热处理前:从220nm减小到45nm).
Nano-sized SrxCa1-xTiO3 solid-solutions have been prepared by low-temperature aqueous synthesis method (LTAS) from cheap starting materials. To improve the morphology and crystallinity of the particles, the hydrothermal post-treatment was followed. The as-obtained powders were analyzed by TEM, XRD, FTIR, TG and ICP measurements. It is shown that as-prepared powders are in form of homogeneous solid solutions of which the crystal structure depends on the composition. Compared with the powders prepared by LTAS method, the powders after hydrothermal post-treatment showed much less hydroxyl defects, higher purity, uniform morphology and better crystallinity. The particle size decreased from 220 nm to 45 nm when the composition Sr increased and somewhat grew after the hydrothermal post-treatment.