Li Linhao, Kler Joe, West Anthony R, De Souza Roger A, Sinclair Derek C
Department of Materials Science and Engineering, University of Sheffield, Sheffield, S1 3JD, UK.
Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany.
Phys Chem Chem Phys. 2021 May 19;23(19):11327-11333. doi: 10.1039/d1cp01120k.
A combination of impedance spectroscopy, time-of-flight secondary ion mass spectrometry and literature data are used to show that, (i) the bulk oxide ion conductivity of A-site, alkaline earth-doped BiFeO3 (BF) is independent of the ionic radius of the alkaline earth ion (Ca, Sr, Ba) and, (ii) despite very different A-site environments in (Na1/2Bi1/2)TiO3 and BF, similar high levels and optimisation of bulk oxide ion conductivity in these Bi-based tilted perovskites is achieved at modest acceptor doping levels of ∼1-10%. These results clearly demonstrate that optimisation of oxide ion conductivity in these materials requires concepts beyond a simple crystallochemical approach based on matching the ionic radii of acceptor dopant and host lattice ions.
结合阻抗谱、飞行时间二次离子质谱和文献数据表明：（i）A位碱土掺杂的BiFeO3（BF）的体相氧化物离子电导率与碱土离子（Ca、Sr、Ba）的离子半径无关；（ii）尽管（Na1/2Bi1/2）TiO3和BF中的A位环境差异很大，但在约1-10%的适度受主掺杂水平下，这些铋基倾斜钙钛矿中仍能实现相似的高体相氧化物离子电导率水平和优化。这些结果清楚地表明，在这些材料中优化氧化物离子电导率需要超越基于匹配受主掺杂剂和主体晶格离子的离子半径的简单晶体化学方法的概念。
