在矿氧化物中量身定制离子排序,用于高温氧化演化反应
Qingxue Liu1,2, Feiran Shen3,4, Guohui Song1,5
1State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
Angewandte Chemie (International ed. in English)
|June 7, 2023
概括
在PrBaCo2-x Fex O5+δ矿中调整离子排序显著影响固体氧化物电解细胞 (SOEC) 中氧化演化反应 (OER) 的性能. A-site 阴离子排序增强了 OER,而氧空位排序阻碍了它,导致了优化的阳极材料.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 固体氧化物电解电池 (SOEC) 是一种
背景情况:
- 矿是固体氧化物电解细胞 (SOEC) 中高温氧化演化反应 (OER) 的有希望的阳极材料.
- 离子排序对矿阳极OER性能的影响仍未得到充分研究,阻碍了合理的材料设计.
研究的目的:
- 研究PrBaCo2-x Fex O5+δ矿中离子排序和OER性能之间的关系.
- 在SOEC中确定最佳的离子排序配置,以增强阳极活性.
主要方法:
- 通过控制的离子排序合成PrBaCo2-x Fex O5+δ矿.
- 物理化学特征 (例如,XRD,TEM,XPS). 物理化学特征 (例如,XRD,TEM,XPS). 物理化学特征 (例如,XRD,TEM,XPS). 物理化学特征 (例如,XRD,TEM,XPS).
- 在SOEC中进行OER性能电化学测试.
- 密度函数理论 (DFT) 计算以了解离子迁移机制.
主要成果:
- 发现现场阴离子排序促进了氧气批量迁移和表面运输,增强了OER活动.
- 观察到氧气空位的排序削弱了OER的性能.
- 具有A位点排序和无序氧空缺的PrBaCo2 O5+δ阳极在800°C和2.0V时达到3.40A cm-2的峰值性能.
结论:
- 离子排序,特别是A位点离子排序,是确定SOECs矿阳极高温OER性能的一个关键因素.
- 了解和控制离子排序为设计优质阳极材料提供了一条道路,以实现高效的SOEC运行.
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