Theoretical study on proton diffusivity in Y-doped BaZrO3 with realistic dopant configurations
Theoretical study on proton diffusivity in Y-doped BaZrO3 with realistic dopant configurations
复制标题
具有实际掺杂剂配置的 Y 掺杂 BaZrO3 中质子扩散率的理论研究
DOI：
10.1039/d0cp06035f
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发表时间：
2021
影响因子：
3.3
通讯作者：
Kasamatsu Shusuke
中科院分区：
文献类型：
--
作者：
Fujii Takeo;Toyoura Kazuaki;Uda Tetsuya;Kasamatsu Shusuke
我们从理论上重新审视了加工条件下具有实际掺杂剂配置的掺钇锆酸钡（掺Y的BaZrO 3）中的质子扩散率。在最近的一项研究中，采用副本交换蒙特卡罗方法，在典型的烧结温度下的平衡Y配置被证明偏离随机配置假设在早期的理论研究。在本研究中，我们考虑到这一观察，并评估了Y配置对质子扩散率的影响。采用基于第一性原理计算的局域扩散势垒的主方程方法，计算了实际Y构型下的质子扩散系数，结果表明实际Y构型下的质子扩散系数高于随机构型下的质子扩散系数.这可以通过以下事实来解释：由于Y掺杂剂的隔离趋势，与随机配置相比，实际的Y配置具有更少的具有深势威尔斯的陷阱位置。此外，质子-质子相互作用和丰富的优先传导途径的影响进行了讨论，它被发现，这两个是相对较小的因素相比，在确定的依赖性的质子扩散率的Y配置的陷阱网站的效果。
We theoretically revisit the proton diffusivity in yttrium-doped barium zirconate (Y-doped BaZrO3) with realistic dopant configurations under processing conditions. In a recent study employing the replica exchange Monte Carlo method, the equilibrium Y configurations at typical sintering temperatures were shown to deviate from the random configuration assumed in earlier theoretical studies. In the present study, we took this observation into account and evaluated the effect of the Y configuration on the proton diffusivity. Using the master equation approach based on local diffusion barriers calculated from first principles, the proton diffusivities under realistic Y configurations were estimated to be higher than those in the random configuration. This is explained by the fact that realistic Y configurations have fewer trap sites with deep potential wells compared to the random configuration due to the isolation trend of Y dopants. In addition, the effects of proton–proton interaction and the abundance of preferential conduction pathways are discussed; it is found that both are relatively minor factors compared to the trap site effect in determining the dependence of the proton diffusivity on the Y configurations.