The role of deep acceptor levels in hydration and transport processes in BaZr1 − xYxO3 – δ and related materials
The role of deep acceptor levels in hydration and transport processes in BaZr1 − xYxO3 – δ and related materials
复制标题
BaZr1 − xYxO3 – δ 及相关材料中深受体水平在水合和运输过程中的作用
DOI：
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发表时间：
2016
影响因子：
2.5
通讯作者：
L. Putilov
中科院分区：
文献类型：
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作者：
V. Tsidilkovski;L. Putilov
考虑到电子、空穴和振动子系统的贡献，发展了受主掺杂质子导电钙钛矿中水合和缺陷形成的统计理论。使用钇掺杂的BaZrO 3作为一个例子，我们表明，深受主状态可以显着影响质子导电氧化物的水合，氧化和运输过程。这些状态对缺陷热力学的影响强烈地依赖于它们的能量，并且在小于一定值的深度处变得可以忽略不计。我们证明了锆酸钡的空穴电导率的实验数据可以用能带输运模型和小极化子跳跃模型来描述。这些情况对应于受体能级的稍微不同的深度，但是在这两种情况下，受体中心处的束缚空穴的浓度可以足够高，并且在缺陷形成考虑中必须考虑这些状态。得到的结果与实验数据的氢的溶解度和不同的载流子（质子，氧离子，空穴）的电荷转移的贡献，在锆酸钡与不同的掺杂水平。
A statistical theory of hydration and defect formation in acceptor-doped proton-conducting perovskites has been developed taking into account contributions of the electron hole and vibrational subsystems. Using yttrium-doped BaZrO3 as an example, we show that deep acceptor states can significantly affect hydration, oxidation, and transport processes in proton-conducting oxides. The impact of these states on defect thermodynamics strongly depends on their energy and becomes negligible at a depth less than a certain value. We demonstrate that the experimental data on the hole conductivity of barium zirconates can be described both in the band transport model and in the model of small polaron hopping. These scenarios correspond to a somewhat different depth of the acceptor levels, but in both cases, the concentration of bound holes at the acceptor centers can be high enough and these states must be taken into account in the defect formation considerations. The results obtained agree well with experimental data on the hydrogen solubility and the contributions of different carriers (protons, oxygen ions, holes) to the charge transfer in barium zirconates with different doping levels.