Atomic-Scale Identification of the Electrochemical Roughening of Platinum
Atomic-Scale Identification of the Electrochemical Roughening of Platinum
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DOI：
10.1021/acscentsci.9b00782
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发表时间：
2019-12-26
影响因子：
18.2
通讯作者：
Koper, Marc T. M.
中科院分区：
文献类型：
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作者：
Jacobse, Leon;Rost, Marcel J.;Koper, Marc T. M.
氧化条件下的电极降解是铂电催化剂大规模应用的主要缺点。已知使Pt（111）经受氧化还原循环会导致纳米岛的生长。我们研究了这种现象，同时在原位电化学扫描隧道显微镜和循环伏安法相结合。在这里，我们提出了一个详细的分析所形成的岛屿，推导出（演变）的平均岛屿生长形状。从岛的形状，我们确定原子尺度的缺陷位置的密度，例如，台阶和刻面，其显示出与不同伏安氢吸附峰的良好相关性。基于电化学扫描隧道显微镜（EC-STM）和CV数据的这种组合，我们得到了详细的原子图像的nanoisland演变过程中的电位循环，提供新的见解铂电极降解的初始阶段。
Electrode degradation under oxidizing conditions is a major drawback for large-scale applications of platinum electrocatalysts. Subjecting Pt(111) to oxidation-reduction cycles is known to lead to the growth of nanoislands. We study this phenomenon using a combination of simultaneous in situ electrochemical scanning tunneling microscopy and cyclic voltammetry. Here, we present a detailed analysis of the formed islands, deriving the (evolution of the) average island growth shape. From the island shapes, we determine the densities of atomic-scale defect sites, e.g., steps and facets, which show an excellent correlation with the different voltammetric hydrogen adsorption peaks. Based on this combination of electrochemical scanning tunneling microscopy (EC-STM) and CV data, we derive a detailed atomistic picture of the nanoisland evolution during potential cycling, delivering new insights into the initial stages of platinum electrode degradation.