表面下化物形成导致Pd的表面吸附过程减缓(111) 单晶电极在酸性电解质中的单晶电极
Xiaoting Chen1,2, Kasinath Ojha2, Marc T M Koper2
1School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, P.R. China.
JACS Au
|October 27, 2023
概括
了解 (Pd) 的电化学是催化剂设计的关键. 这项研究表明,由于地下气的形成,Pd{111}上的离子吸附速度很慢,这影响了催化剂的性能.
科学领域:
- * 表面科学和电化学
- * 材料科学和催化剂
背景情况:
- * 作为异质催化和电化学中的催化剂的关键作用.
- *对单晶电极的电化学过程和界面现象的理解有限.
- *需要对不同电解质条件下的电极行为进行详细研究.
研究的目的:
- *为了研究 (Pd(111)) 电极的电化学行为.
- * 分析离子吸附/脱附动力学和界面现象.
- * 阐明地下气形成在电化学中的作用.
主要方法:
- *循环电压测量 (CV) 用于研究电化学反应和电位依赖现象.
- *电化学阻抗光谱 (EIS) 探测界面特性和反应动力学.
- * 用各种酸性电解质 (硫酸,酸盐,甲硫酸和酸) 进行的实验.
主要成果:
- * 阳离子 (HSO4-,ClO4-,CH3SO3-,F-) 在低电位时表现出强烈的吸附,与低电位沉积 (UPD-H) 叠加.
- * 这些离子在更高的电位上与表面基相吸附并相互作用.
- * 阳离子吸附/脱附是一个动力学上缓慢的过程,与地下吸收和形成化 (PdHx) 相关,从0.40V左右开始.
- * 地表显著改变了工作功能,影响了离子吸附/脱附动力学,并导致不可逆转的电压峰值.
结论:
- * 地下气的形成是影响离子吸附/脱附动力学在Pd上的关键因素.
- * 地下,化物和吸附的离子之间的相互作用决定了界面行为.
- * 这种理解对于推进单晶的基础研究和优化电催化剂至关重要.
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