Speaker:

Prof. Soren Bertelsen Scott, University of Copenhagen.

Tittle: Probing OER Intermediates with Light and Molecules

Time: 15:00 May 20th, 2026 (Wednesday)

Venue: Conference Room 5, Building No.5

Host: Prof. Zhiyong Tang

Abstract:

Stability and catalytic activity of metal oxides for the water oxidation at an electrolyzer anode are linked through the reactivity of oxygen atoms: metal–oxygen bonds are formed and broken during the electrocatalytic cycle, and metal–oxygen bonds are also what holds the material together. One way to probe this interplay is by isotope labelling of the oxygen in the electrocatalyst with ¹⁸O and determining by electrochemistry – mass spectrometry (EC-MS) whether this labelled oxygen is incorporated into the O₂ released. Through our work with chip EC-MS on sputter-deposited ¹⁸O-labelled oxides of Ru and Ir, we show the importance of quantitative and transparent data analysis in such oxygen-tracking experiments and their limitations. We then expand on the concept using CO oxidation, showing how the incorporation of labelled oxygen into the product CO₂ probes the reactivity of pre-catalytic surface states. A more direct probe of these states is to observe them spectroscopically. We show through fitting the UV-vis spectra of iridium oxide as a function of potential that the pre-catalytic redox transitions on electrodeposited IrOx follow Frumkin isotherms, and propose a way of quantifying the relative importance of chemical vs electrochemical driving force in the rate-determining step.

Info.:

Soren Bertelsen Scott is an assistant professor at the University of Copenhagen, Department of Chemistry. His research employs novel experimental methods and model surfaces to unravel the mechanisms of electrocatalytic reactions such as water oxidation to O₂ and CO₂ reduction to ethylene that will play important roles in chemical industry because of the green energy transition. Soren also develops open-source packages to facilitate open science and data-driven approaches to fundamental catalysis development. Soren has his bachelors in Chemistry from UCPH in 2013, masters in Chemical Engineering from the Technical Unviersity of Denmark (DTU) in 2016, and PhD in Physics from DTU in 2019 under the supervision of Professor Ib Chorkendorff. He spent a year at the start-up company Spectro Inlets A/S before doing a postdoc from 2021 to 2023 at Imperial College London in the group of Ifan E. L. Stephens. For more on Soren's research, see: https://chem.ku.dk/research_sections/nanochem/scott-group