Effect of Synthesis Process on CuO Segregation and Dielectric Properties of CaCu3Ti4O12 Ceramic  

作　　者：CHEN Yuan TENG Yuancheng 陈元;滕元成;ZHAO Xiaofeng;WU Lang(State Key Laboratory for Environment-friendly Energy Materials,Southwest University of Science and Technology,Mianyang 621010,China;School of Materials Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]State Key Laboratory for Environment-friendly Energy Materials,Southwest University of Science and Technology,Mianyang 621010,China [2]School of Materials Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2019年第5期1089-1096,共8页武汉理工大学学报（材料科学英文版）

摘　　要：The CaCu3Ti4O12(CCTO) ceramic was prepared through conventional solid-state method. The effects of synthesis process(synthesis temperature and synthesis time) of powder on ceramic microstructures, CuO segregation and electrical properties were investigated. The phase composition was determined by X-ray diffraction and the microstructure was examined by SEM. The dielectric constant, dielectric loss, and resistance of the ceramic were also determined by a precision impedance tester. The results show that, as the synthesis temperature increases, the CCTO ceramic grain size decreases and the stoichiometric ratio of Cu/Ca at the grain boundary increases, the dielectric constant increases and the dielectric loss decreases(40 < f < 10 kHz). In addition, when the synthesis time is shorter than 12 h, the Cu/Ca ratio of CCTO decreases and the dielectric constant increases with time increase. However, when the synthesis time exceeds 12 h, this trend is just the opposite. It is further proved that Cu at the grain boundary is not conducive to the dielectric constant of CCTO.The CaCu3Ti4O12（CCTO） ceramic was prepared through conventional solid-state method. The effects of synthesis process（synthesis temperature and synthesis time） of powder on ceramic microstructures, CuO segregation and electrical properties were investigated. The phase composition was determined by X-ray diffraction and the microstructure was examined by SEM. The dielectric constant, dielectric loss, and resistance of the ceramic were also determined by a precision impedance tester. The results show that, as the synthesis temperature increases, the CCTO ceramic grain size decreases and the stoichiometric ratio of Cu/Ca at the grain boundary increases, the dielectric constant increases and the dielectric loss decreases（40 < f < 10 kHz）. In addition, when the synthesis time is shorter than 12 h, the Cu/Ca ratio of CCTO decreases and the dielectric constant increases with time increase. However, when the synthesis time exceeds 12 h, this trend is just the opposite. It is further proved that Cu at the grain boundary is not conducive to the dielectric constant of CCTO.

关 键 词：CACU3TI4O12 SYNTHESIS temperature SYNTHESIS time microstructure DIELECTRIC properties 

分 类 号：TQ1[化学工程]