Keynote Talk - Thursday, 16 September I 9:35 AM (CEST)
Prof. Martin Edwards: "Nanoscale scanned electrochemical probe microscopy"
Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas, USA
Electrochemical reactions drive numerous industrially important processes and technologies, such as batteries, fuel cells, electrochemical syntheses, and sensors. These reactions take place at the surface of heterogeneous electrodes, e.g., electrocatalytic nanoparticles on a carbon support used in fuel cells, battery electrodes built from a mixture of active material, additives and mechanical binder, etc. Even ‘simple’ single material electrodes contain defects and sites (crystallographic grains, grain boundaries, step edges, defects, etc.). Heterogeneous electrodes have heterogenous electrochemical behaviors, to gain deep understanding of processes on electrode surfaces requires a spatially-resolved view of the electrochemical reactions.
Classical electrochemical methods characterize electrodes or devices by electrically connecting the entire device and measuring the current or voltage response. This quantifies the overall behavior, averaging out that of the individual electrode components. Scanned electrochemical probe microscopy employs nanoelectrodes and nanopipettes as a probe to measure the current/voltage response in a small portion of the electrode surface (~10 nm to ~1 μm). Repeating measurements in a raster pattern creates a map of the electrochemical characteristics of electrode surfaces, allowing us to assess heterogeneity and the behavior of individual components.
In this talk, I will provide an introduction to scanned electrochemical probe microscopy. Using exemplar systems, we will discuss the operating principles, instrumentation, and measurable quantities. No prior experience of electrochemistry is required.