Al掺杂对CaCu_3Ti_4O_(12)陶瓷介电性能的影响

Influence of Al doping on the dielectric properties of CaCu_3Ti_4O_(12) ceramics

采用标准电子陶瓷工艺,制备了CaCu3Ti4-xAlxO12-x/2(CCTAO,x=0,0.06,0.10,0.20)陶瓷样品,研究Al对CCTAO材料的微观结构和介电性能的影响.结果表明,Al的添加可促进CaCu3Ti4O12(CCTO)晶界处小晶粒生长,拟制大晶粒长大,增强晶界的绝缘性,使低频介电弛豫行为明显减弱,降低了CCTAO陶瓷样品低频范围的介电损耗.x=0.2时在40 Hz^1 kHz频率范围内,tanδ均小于0.05,最小值仅为0.033.对该样品偏压下的介电性能的研究发现,Al3+取代Ti4+可实现P型掺杂,改变基体的半导状态,拟制表面作用,从而使样品低频范围受偏压影响明显减弱.

The CaCu3Ti4-xAlxO12-x/2(CCTAO)(x=0,0.06,0.10,0.20) ceramics is prepared by the solid-state reaction.The effect of Al on the dielectric properties and microstructure revolution of CCTAO ceramics are studied.The results indicate that Al-doping improve the growth of small grain and prevent that of the large grain at grain boundary.Meanwhile,the increase of insulating performance of grain boundary lead to the dielectric relaxation properties at lower frequency obviously weakened and the dielectric loss at lowe...