钽酸盐Ba_5YTi_3Ta_7O_(30)的X射线衍射分析及其介电特性

X-ray Diffraction Analysis of Tantalate Ba_5YTi_3Ta_7O_(30) andIts Dielectric Properties

在BaO -TiO2-Ta2O5 体系中通过掺Y3 +合成了钽酸盐Ba5YTi3Ta7O30,采用粉晶X射线衍射 (XRD)对其结构进行了分析 ,并测试了其陶瓷体的介电特性;结果表明 ,Ba5YTi3Ta7O30 在室温下属于填满型四方钨青铜结构顺电相,晶胞参数为a=1.24387(2)nm,c=0.39178(1)nm ,α= β=γ=90° ;频率为1MHz时Ba5YTi3Ta7O30 陶瓷的室温相对介电常数为155 ;而且介电损耗低至0.0009。

A tantalate Ba5YTi3Ta7O30 was synthesized by doping Y3+ in the ternary system BaO-TiO2-Ta2O5. The crystal structure was determined by X _ ray powder diffraction, and it belongs to tetragonal tungsten bronze structure at room temperature with unit cell parameters,a=1.243 87(2)nm, c=0.391 78(1) nm, α=β=γ=90°. Further, dielectric properties measurements showed that the relative dielectric constant(εr) of Ba5YTi3Ta7O30 ceramic attained 155, combined with a low dielectric loss of 0.000 9 at 1 MHz.