Platinum electrochemistry through a magnifying glass
In most applications, electrocatalysts exhibit a large surface area to volume ratio, for example using nanoparticles.
- Jacobse, L.
- 29 november 2018
- Thesis in Leiden Repository
In most applications, electrocatalysts exhibit a large surface area to volume ratio, for example using nanoparticles. To fully understand fundamental electrochemical processes at the length scale of these nanoparticles, it is necessary to use specialized experimental techniques. In this thesis, the stability and activity of platinum electrode surfaces are studied at the nano- and micrometer scale using Electrochemical Scanning Probe Microscopy (EC-SPM) techniques. Chapters 2 and 3 describe the roughening of an atomically flat Pt(111) surface upon repetitive oxidation and reduction. These data were acquired using a combination of Electrochemical Scanning Tunneling Microscopy (EC-STM) and Cyclic Voltammetry (CV). Chapter 4 describes the development of a new technique to resolve small differences in local reactivity: voltammetric Scanning Electrochemical Cell Microscopy (SECCM). The power of this technique is demonstrated by studying the reactivity of a polycrystalline Pt sample towards hydrazine oxidation. Finally, Chapter 5 compares the reactivity of small Pt ultramicroelectrodes to that of conventional macroelectrodes.