Identical location scanning electron microscopy (IL–SEM) has become an important tool for electrocatalysis research in the past few years. The method allows for the observation of the same site of an electrode, often down to the same nanoparticle, before and after electrochemical treatment. It is presumed that by IL–SEM, alterations in the surface morphology (the growth, shrinkage, or the disappearance of nanosized features) can be detected, and the thus visualized degradation can be linked to changes of the catalytic performance, observed during prolonged electrolyses. In the rare cases where no degradation is seen, IL–SEM may provide comfort that the studied catalyst is ready for up-scaling and can be moved towards industrial applications. However, although it is usually considered a non-invasive technique, the interpretation of IL–SEM measurements may get more complicated. When, for example, IL–SEM is used to study the degradation of surfactant-capped Ag nanocubes employed as electrocatalysts of CO₂ electroreduction, nanoparticles subjected to the electron beam during pre-electrolysis imaging may lose some of their catalytic activity due to the under-beam formation of a passive organic contamination layer. Although the entirety of the catalyst obviously degrades, the spot mapped by IL–SEM reflects no or little changes during electrolysis. The aim of this paper is to shed light on an important limitation of IL–SEM: extreme care is necessary when applying this method for catalyst degradation studies, especially in case of nanoparticles with surface-adsorbed capping agents.

过去几年，相同的位置扫描电子显微镜（IL-SEM）已成为电催化研究的重要工具。该方法允许在电化学处理之前和之后观察电极的相同部位，通常观察到相同的纳米颗粒。据推测，通过IL–SEM，可以检测到表面形态的变化（纳米尺寸特征的生长，收缩或消失），并且由此可见的降解可以与长时间电解过程中观察到的催化性能变化相关。 。在极少见的降解情况下，IL–SEM可以使研究的催化剂可以按比例放大，并可以用于工业应用，从而提供安慰。但是，尽管通常认为它是非侵入性技术，IL–SEM测量的解释可能会变得更加复杂。例如，当使用IL–SEM研究用作CO电催化剂的表面活性剂封端的Ag纳米立方体的降解时_在图2的电还原中，在预电解成像期间经受电子束的纳米粒子可能由于在束下形成无源有机污染层而失去一些催化活性。尽管整个催化剂明显降解，但IL-SEM绘制的斑点在电解过程中几乎没有变化。本文的目的是阐明IL-SEM的一个重要局限性：将这种方法用于催化剂降解研究时，特别是在纳米粒子表面吸附有封端剂的情况下，必须格外小心。