低温—低压水热合成Ba1—xSrxTi1—ySnyO3纳米材料及其结构与性能研究

Hydrothermal Synthesis, Structure and Property of Ba1- xSrxTi1- ySnyO3 Nanometer Materials

采用低温-低压水热法,在150℃,0.5 MPa以下合成了一系列Ba1-xTrxTi1-ySnyO3固溶体纳米粉末(0≤x≤0.5,0≤y≤0.4),经XRD物相分析和d-间距-组成图证明,产品为立方晶系的完全互溶取代固溶体,结果符合Vegard定律.TEM形貌观察,粒子为均匀球形,平均粒径80nm.通过制陶实验,分别测定了该系列固溶体的室温介电常数、介电损失以及介电常数随温度的变化.结果发现,用该方法在BaTiO3中掺入适量锶和锡,由于掺杂离子均匀进入母体晶格,引起Tc降低,介电性能改善显著.当x＝0.1,y＝0.08时,室温介电常数达17 000,比BaTiO3纯相提高10倍,而介电损失却降低88%.

A series of Ba1-xSrxTi1-ySnyO3 (0 less than or equal to x less than or equal to 0. 5, 0 less than or equal to y less than or equal to 0.4) solid solutions were synthesized by low - temperature/low - pressure hydrothermal method below 150 degreesC, 0.5 MPa. XRD pattern and cell parameters - composition figures of these prepared powders demonstrated that they were completely miscible solid solutions in BaTiO3. Furthermore, TEM showed that they were uniform, substantially spherical particles with an average particle size of 80 nm in diameter. The sintered ceramics of those powders doped by Sr2+ and Sn4+ had dielectric constant ten times higher and dielectric loss six times lower than pure BaTiO3 phase at room temperature.