Nb5+掺杂对(Ca0.97Ba0.03)Cu3Ti4O12陶瓷结构与电性能的影响

该文利用固相反应法制备了(Ca0.97Ba0.03)Cu3Ti4-xNbxO12 (x=0,0.01,0.03,0.05,0.07,0.10,0.15,0.20， 摩尔分数)陶瓷。借助X线衍射仪及扫描电子显微镜研究了Nb5+的摩尔分数对(Ca0.97Ba0.03)Cu3Ti4O12陶瓷的相结构及表面微观形貌的影响，借助高低温介电测试系统和阻抗测试仪获得了(Ca0.97Ba0.03)Cu3Ti4-xNbxO12陶瓷电性能变化规律。结果表明，各组分(Ca0.97Ba0.03)Cu3Ti4-xNbxO12陶瓷均为单相立方钙钛矿结构；Nb5+摩尔分数的增加可抑制(Ca0.97Ba0.03)Cu3Ti4-xNbxO12陶瓷晶粒的生长并消除其晶粒异常长大；适量掺杂 Nb+能够有效提高(Ca0.97Ba0.03)Cu3Ti4-xNbxO12陶瓷的晶界电阻，从而降低其介电损耗，且可提高(Ca0.97Ba0.03)Cu3Ti4-xNbxO12陶瓷相对介电常数的温度稳定性。

Influences of Nb5+ Doping on Structure and Electric Properties of (Ca0.97Ba0.03)Cu3Ti4O12 Ceramics

The (Ca0.97Ba0.03)Cu3Ti4-xNbxO12(x=0,0.01,0.03,0.05,0.07,0.10,0.15,0.20) ceramics have been prepared by the solid state reaction method. The influences of the mole fraction of Nb5+ on the phase structure and surface micromorphology of (Ca0.97Ba0.03)Cu3Ti4O12 ceramics have been investigated using the X ray diffractometer and scanning electron microscope. The variations of the electric properties of the (Ca0.97Ba0.03)Cu3Ti4-xNbxO12 ceramics are obtained by the high and low temperature dielectric performance test system and impedance tester. The results show that the (Ca0.97Ba0.03)Cu3Ti4-xNbxO12 ceramics of various components are single phase cubic perovskite structure. With the increase of the mole fraction of Nb5+, the grain growth of (Ca0.97Ba0.03)Cu3Ti4-xNbxO12 ceramics can be inhibited effectively and the abnormal grain growth is eliminated. The grain boundary resistance of (Ca0.97Ba0.03)Cu3Ti4-xNbxO12 ceramics can be effectively increased by appropriately doping Nb5+, thus its dielectric loss can be reduced, and the temperature stability of the relative dielectric constant of (Ca0.97Ba0.03)Cu3Ti4-xNbxO12 ceramics can also be improved.