Density Functional Theory Study of Dopant Effect on Sintering in the Anode of Solid Oxide Fuel Cell
Density Functional Theory Study of Dopant Effect on Sintering in the Anode of Solid Oxide Fuel Cell
复制标题
固体氧化物燃料电池阳极掺杂对烧结影响的密度泛函理论研究
DOI：
10.1149/06801.3187ecst
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
and Momoji Kubo
中科院分区：
文献类型：
--
作者：
Jingxiang Xu;Yuji Higuchi;Nobuki Ozawa;Kazuhisa Sato;Toshiyuki Hashida;and Momoji Kubo
Ni/Y掺杂的ZrO2阳极中Ni颗粒的烧结是固体氧化物燃料电池广泛应用的主要障碍。本文通过密度泛函理论计算，研究了掺杂(Y和Al)对Ni原子在ZrO2表面扩散的影响，以抑制烧结。Ni原子在掺Al表面和掺Y表面上最稳定的吸附位置分别是双配位氧原子附近和氧空位附近。发现Al掺杂的ZrO2表面的最稳定吸附能大于Y掺杂的ZrO2表面的最稳定吸附能。基于Ni原子在两个表面上的势能面的扩散路径分析表明，Ni原子在Al掺杂的ZrO2表面上的扩散能垒大于在Y掺杂的ZrO2表面上的扩散能垒。Ni原子在Al掺杂的ZrO2表面的扩散比在Y掺杂的ZrO2表面的扩散更为困难。这是因为Ni原子强烈结合在双配位氧原子上，而Ni原子被约束在Al掺杂的ZrO2表面。因此，与Y掺杂的表面相比，Al掺杂的ZrO2表面的Ni烧结受到了抑制。
Sintering of Ni particles in the Ni/Y-doped ZrO2 anode is a major obstacle to the widespread use of solid oxide fuel cell. In this study, we investigated the dopant effect on the diffusion of a Ni atom on the ZrO2 surface with dopants (Y and Al) by density functional theory calculations in order to inhibit the sintering. The most stable adsorption sites of the Ni atom on the Al-doped and Y-doped ZrO2 surfaces are the vicinity of the twofold-coordination oxygen atom and the vicinity of an oxygen vacancy, respectively. It is found that the most stable adsorption energy on the Al-doped ZrO2 surface is larger than that on the Y-doped ZrO2 surface. The analysis of diffusion path based on the potential energy surfaces of the Ni atom on the two surfaces shows that the energy barrier for the diffusion of the Ni atom on the Al-doped ZrO2 surface is larger than that on the Y-doped ZrO2 surface. The diffusion of the Ni atom on the Al-doped ZrO2 surface is more difficult than that on the Y-doped ZrO2 surface. This is because the Ni atom strongly bound to the twofold-coordination oxygen atom and the Ni atom is constrained in the Al-doped ZrO2 surface. Thus, the Ni sintering on the Al-doped ZrO2 surface is inhibited compared to that on the Y-doped ZrO2 surface.