Nb^5+掺杂对(Ca0.97Ba0.03)Cu3Ti4O12陶瓷结构与电性能的影响

Influences of Nb^5+Doping on Structure and Electric Properties of(Ca0.97Ba0.03)Cu3Ti4O12 Ceramics

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Nb^5+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;Nb^5+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。

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 Nb^5+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 Nb^5+,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 Nb^5+,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.