Dielectric properties and electrical response of yttrium-doped Bi_(2/3)Cu_(3)Ti_(4)O_(12)ceramics  

作　　者：Longhai Yang Luwen Song Qi Li Tao Zhang 

机构地区：[1]School of Electrical and Control Engineering Xi’an University of Science and Technology Xi’an 710054,Shaanxi,P.R.China [2]School of Materials Science and Engineering Shaanxi Normal University,Xi‘an 710062,Shaanxi,P.R.China [3]School of Science,Xi’an University of Science and Technology Xi’an 710054,Shaanxi,P.R.China

出　　处：《Journal of Advanced Dielectrics》2021年第1期47-54,共8页先进电介质学报（英文）

基　　金：This work was supported by National Natural Science Foundation of China(NSFC)(Grant Nos.51902193 and 11974275);The Shaanxi Province Key Science and Technology Innovation Team Project(Grant No.2019TD-026);Natural Science Basic Research Plan in Shaanxi Province of China(2019JQ-092);the China Postdoctoral Science Foundation(2019M663617 and 2019TQ0191);Scientific Research Plan Projects of Shaanxi Province Education Department(CN)(20JK0755).

摘　　要：(YxBi_(1-x))_(2/3)Cu_(3)Ti_(4)O_(12)(x=0.00-0.30)ceramics were successfully prepared via the conventional solid-state method.X-ray powder diffraction confirmed the lattice constant gradually decreases with increasing Y^(3+)content.SEM images displayed Y^(3+)substitution for Bi^(3+)gave rise to the large abnormal grains,and the size of abnormal grains became larger with the increase of Y^(3+)substitution.(YxBi_(1-x))_(2/3)Cu_(3)Ti_(4)O_(12)ceramics presented the relatively high dielectric constant of 7400 with the dielectric loss of 0.055 when x=0.20.The analysis of complex impedance suggested the grains are semiconductive and the grain boundaries are insulating.For pure Bi_(2/3)Cu_(3)Ti_(4)O_(12)ceramics,the appearance of additional low-frequency peaks in electrical modulus indicated the grain boundaries are heterogeneous.The investigation of modulus peaks fitting with Arrhenius formula implied that the low-frequency permittivity for all(YxBi_(1-x))_(2/3)Cu_(3)Ti_(4)O_(12)ceramics was ascribed to the Maxwell-Wagner relaxation at grain boundaries.In addition,a set of clear dielectric peaks above 200℃associated with Maxwell-Wagner relaxation can be found for all(YxBi_(1-x))_(2/3)Cu_(3)Ti_(4)O_(12)ceramics in the temperature dependence of dielectric constant.This set of clear dielectric peaks showed a tendency to shift to higher temperatures with the increase of Y^(3+)substitution.Meanwhile,a tiny dielectric anomaly at room temperature was found in Y-doped Bi_(2/3)Cu_(3)Ti_(4)O_(12)ceramics.

关 键 词：CERAMICS MICROSTRUCTURE dielectric properties impedance spectroscopy 

分 类 号：TQ1[化学工程]