Mo掺杂SrBi_4Ti_4O_(15)陶瓷的铁电介电性能

Ferroelectric and dielectric properties of Mo-doped SrBi_4Ti_4O_(15) ceramics

用传统的固相烧结工艺,制备了钼掺杂铁电陶瓷样品SrBi4Ti4O15(SBTi)铁电陶瓷SrBi4-2x/3Ti4-xMoxO15(x=0.00,0.003,0.012,0.03,0.06,0.09).X射线衍射的结果表明,样品均为单一的层状钙钛矿结构相,Mo掺杂未改变SBTi的晶体结构.通过扫描电子显微镜观测发现,样品晶粒为片状,随掺杂量的增加,晶粒逐渐变小.铁电测量表明,Mo掺杂使SBTi的铁电性能得到较大改善.随掺杂量x的增加,样品的剩余极化(2Pr)呈现出先增大,后减小的规律.在x=0.06时,2Pr达到最大值26.5μC/cm2,与SrBi4Ti4O15(2Pr=12.2μC/cm2)相比,提高117%.材料的矫顽场Ec在掺杂后增加仅为20%左右.SBTi的居里温度受掺杂的影响甚微,说明Mo对SrBi4Ti4O15的掺杂基本未影响材料原有的良好的热稳定性.

The ferroelectric ceramics samples of SrBi4-x3Ti4-xM%O15 （x = 0.00, 0.003, 0.012, 0.03, 0.06, 0.09） have been prepared by the conventional solid-state reaction method. X-ray diffraction analysis shows that the crystal structure of SrBi4Ti4 O15 （SBTi） is not affected by Mo-dopiag. The scanning electronics microscope （SEM） images indicate that all the samples consist of sheet grains and the grain size is reduced by Mo-doping while the ferroeleetrie properties are improved significantly. The remanent polarization （2Pr） increases at first,then decreases with the inereasiag Mo content. At x = 0.06, the 2Pr maximizes at a value of 26.5 μC/cm^2 , which about 117% higher in comparison with that of SBTi. And the coercive field of SBTi is increased only about 20%. The Curie temperature of the samples varied slightly after doping, which implies that the good thermal stability of SBTi is not sacrificed.