Lemineur Jean-François, Noël Jean-Marc, Combellas Catherine, Ausserré Dominique, Kanoufi Frédéric
Université Sorbonne Paris Cité, Université Paris Diderot, ITODYS, CNRS UMR 7086, 15 rue J. de Baïf, F-75013 Paris, France.
Faraday Discuss. 2018 Oct 1;210(0):381-395. doi: 10.1039/c8fd00037a.
The interest in nano-objects has recently dramatically increased in all fields of science, and electrochemistry is no exception. As a consequence, in situ and operando visualization of electrochemical processes is needed at the nanoscale. Herein, we propose a new interferometric microscopy based on an antireflective thin metal electrode layer. The technique is coupled to electrochemistry in a model example: the electro-deposition of Ag metallic nanoparticles (NPs). This challenges the current opto-electrochemical methods and even those relying on nano-impact detection. Indeed, the sensitivity allows the dynamic in situ visualization of the electrochemical growth and dissolution of individual Ag NPs, whose size was tracked dynamically down to 15 nm in diameter. The use of microelectrodes provides interesting quantitative analysis of the NPs, from optically resolved arrays of single NPs to condensed arrays of (unresolved) NPs. Particularly, the optical analysis of all the individual NPs allows the reconstruction of optical voltammograms similar to the electrochemical ones. Finally, the NP dissolution-redeposition is also investigated.
近年来，纳米物体在所有科学领域的关注度都急剧上升，电化学领域也不例外。因此，需要在纳米尺度上对电化学过程进行原位和实时可视化。在此，我们提出了一种基于抗反射薄金属电极层的新型干涉显微镜。该技术在一个模型示例中与电化学相结合：银金属纳米颗粒（NPs）的电沉积。这对当前的光电化学方法甚至那些依赖纳米冲击检测的方法提出了挑战。事实上，这种灵敏度使得能够动态原位可视化单个银纳米颗粒的电化学生长和溶解过程，其尺寸在动态跟踪中可小至直径15纳米。微电极的使用为纳米颗粒提供了有趣的定量分析，从光学分辨的单个纳米颗粒阵列到（未分辨的）纳米颗粒凝聚阵列。特别是，对所有单个纳米颗粒的光学分析允许重建类似于电化学伏安图的光学伏安图。最后，还研究了纳米颗粒的溶解 - 再沉积过程。
