Journal of Materiomics ( IF 8.4 ) Pub Date : 2020-08-08 , DOI: 10.1016/j.jmat.2020.07.010 Burhan Ullah , Wen Lei , Xianwei Wang , Bihui Zhang , Wen-Zhong Lu
(Sr0.4Ce0.4)1-xNdxTi0.8Mg0.2O3 [(SC)NdTMgO3, x = 0.1–0.4] non-stoichiometric system were obtained through conventional solid-state synthesis technique. All perovskite peaks were attributed to either single (x ≤ 0.3) and/or mixed (x = 0.4) like phases. A solid solution of cubic structure was obtained for x ≤ 0.2, however, for x ≥ 0.3, the (SC)NdTMgO3 compound, exhibits structure instability and (200)/(310) peaks splitting. The peaks splitting indicates cubic (C-phase) to tetrogonal (T-phase) structure phase transition. All ceramic samples appear nearly dense, presenting a non-uniform grain size distribution. The observed trend of the microwave dielectric properties (εr, τf, Q × f) is mainly related to the formation of structure phase transition, packing fraction, relative density and ionic polarizability. A key microwave (MW) dielectric properties of εr = 53, Q × f = 26,700 GHz and τf = +2.8 pmm/°C could be obtained for composition with x = 0.4.
中文翻译:
无线通信非化学计量(Sr 0.4 Ce 0.4)1-x Nd x Ti 0.8 Mg 0.2 O 3系统的结构不稳定性和高微波介电常数
(Sr 0.4 Ce 0.4)1- x Nd x Ti 0.8 Mg 0.2 O 3 [(SC)NdTMgO 3,x = 0.1-0.4]非化学计量体系是通过常规固态合成技术获得的。所有钙钛矿的峰归因于任一单一的(X ≤0.3)和/或混合(X = 0.4)等相。为得到立方结构的固溶体X ≤0.2,但是,对于X ≥0.3,则(SC)NdTMgO 3化合物显示结构不稳定性和(200)/(310)峰分裂。峰分裂表明立方(C相)到四方(T相)结构相变。所有陶瓷样品看起来几乎都是致密的,呈现出不均匀的粒度分布。观察到的微波介电特性(εr,τf,Q×f)的趋势主要与结构相变的形成,堆积分数,相对密度和离子极化率有关。一个关键的微波(MW)的介电特性ε - [R = 53,Q×F = 26700 GHz和τ ˚F = 2.8 PMM /℃可以用于与组合物获得X = 0.4。