Preparation and dielectric properties of Ba4-xSm2Fe2-xNb8 xO30 tungsten bronze ceramics with an adjustable structure that changes from filled to unfilled
Preparation and dielectric properties of Ba4-xSm2Fe2-xNb8 xO30 tungsten bronze ceramics with an adjustable structure that changes from filled to unfilled
复制标题
填充与未填充结构可调的Ba4-xSm2Fe2-xNb8 xO30钨青铜陶瓷的制备及介电性能
DOI：
10.1016/j.materresbull.2019.02.003
复制
发表时间：
2019
影响因子：
5.4
通讯作者：
Fang Liang
中科院分区：
文献类型：
--
作者：
Guo Zhe;Wu Shan;Hu Changzheng;Liu Laijun;Fang Liang
采用标准固相烧结方法制备了名义分子式为Ba4-xSm2Fe2−xNb8+xO30(BSFN)（x = 0、0.025、0.05、0.075和0.1）的钨青铜（TB）结构陶瓷。系统研究了Ba2+浓度对晶相、显微结构、介电和铁电性能的影响。所有化合物均呈现四方钨青铜（TTB）结构，其中A1和A2位点分别仅被Sm3+和Ba2+离子占据，而Fe3+和Nb5+离子随机分布在B1和B2位点之间。所有 BSFN 陶瓷都表现出正常的铁电行为，但介电性能随着 Ba2+ 浓度的降低而表现出分散性增加。导电行为是由于块体和晶界引起的，随着Ba2+浓度的降低，直流电导率从0.67增加到0.77eV。所有BSFN陶瓷的极化-电场(P-E)和电流-电场(I-E)环都表现出铁电行为，并且随着Ba2+浓度的降低，P-E环变得更倾斜和更细。
Tungsten bronze (TB) structural ceramics with the nominal formula Ba4-xSm2Fe2−xNb8+xO30(BSFN) (x = 0, 0.025, 0.05, 0.075 and 0.1) were prepared using a standard solid-state sintering method. The effects of Ba2+concentration on the crystallographic phase, microstructure, dielectric and ferroelectric properties were systematically studied. All compounds presented tetragonal tungsten bronze (TTB) structures, where the A1 and A2 sites were exclusively occupied by Sm3+and Ba2+ions, respectively, while the Fe3+and Nb5+ions were randomly distributed between the B1 and B2 sites. All BSFN ceramics exhibited normal ferroelectric behavior, but the dielectric properties showed an increasing dispersion as the concentration of Ba2+decreased. The conductive behavior was due to the bulk and grain boundaries, and the direct current conductivity was increased from 0.67 to 0.77 eV with a reduction in the concentration of Ba2+. The polarization-electric field (P-E) and current-electric field (I-E) loops of all the BSFN ceramics showed ferroelectric behavior, and the P-E loops became more slanted and slimmer with reduced Ba2+concentration.