Tracking Surface Charge of Gold Single-Crystal Electrodes with Diffuse Layer Force Microscopy
Abstract
Electrochemistry is a powerful approach for the interconversion of electrical and chemical energy. This is enabled by the nanoscale confined potential difference occurring at an interface, such as that between a solid and a liquid. As such, the structure of this region of separated charge, or electrical double layer, inherently includes molecular scale ordering in the liquid, as well as atomic scale details of the electrode, making it challenging to obtain a detailed picture of the potential-dependent state of electrochemical interfaces. In this work, we locally measure the long-range electrostatic interaction force (on the order of the screening length) between single-crystal gold electrodes and a microscale probe. Using such force spectroscopy, we observe three distinct electrochemical phenomena through the interaction force, i.e. non-faradaic charging of the interface and the potential of zero free charge, potential-induced surface reconstruction, and electrochemical oxidation of the gold surface. The results are interpreted within the Derjaguin-Landau-Verwey-Overbeek framework, relating the force measurement to the surface charge and the electrochemical state of the interface.
Authors 3
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Affiliation as printed
Leiden Institute of Chemistry
Leiden University
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Affiliation as printed
Leiden Institute of Chemistry
Leiden University
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Affiliation as printed
Leiden Institute of Chemistry
Leiden University