סמינר בכימיה פיזיקלית: Correlating Transient Events at the Solid-Liquid Interface – Spectroscopic Studies of the Electric Double Layer

Zoom: https://tau-ac-il.zoom.us/j/87820055721?pwd=kewAaVRPgfvQXtUuQD41aWPtcLcecQ.1

Abstract:

The carbon dioxide electroreduction reaction (CO₂RR) and carbonate mineralization are promising interfacial reactions that can significantly contribute to the energy transition, particularly in applications such as seasonal renewable energy storage and carbon sequestration1-3. These processes are essential for mitigating anthropogenic climate change. A deep understanding of the elementary reactions occurring at electrified solid-liquid interfaces, especially the behaviour of the electric double layer (EDL), is critical for optimizing these technologies. However, accurately characterizing reactions at these interfaces poses significant challenges. In our recent work4, we developed a novel approach to identify and disentangle the various physicochemical features of the EDL, including the Stern layer, the diffuse double layer, and concentration gradients extending toward the bulk. This method, termed Dynamic Response Spectroscopy (DRS), utilizes time-variant analysis to distinguish these components. By combining modulated excitation spectroscopy, homodyne detection, and low-rank matrix reconstruction, we achieve several key advantages: (1) suppression of noise, often exceeding 99% of the recorded intensity in spectroelectrochemical measurements; (2) detection of minor but critical contributions from reaction intermediates; and (3) spectroscopic separation of surface intermediates from distinct EDL features. 

This dynamic operando spectroscopic approach addresses common challenges in the operando spectroscopy of electrocatalysis, such as the weak signals of reaction intermediates. With this method, we uncovered novel insights, including the local restructuring of the EDL, the kinetic role of ice-like water layers in CO₂RR, and the influence of solvated cations on reaction pathways. These findings provide a deeper understanding of the elusive nature and behaviour of the (electrified) solid-liquid interface and its critical impact on reaction efficiency. 

References:

1. C. Vogt, and B. M. Weckhuysen, Nat. Chem. Rev. 2022, 6, 89-111.

2. N. Karo, G. Itov, O. Mayraz, C. Vogt, Chem. Eng. J., 2024, 500, 156380.

3. O. Mayraz, N. Karo, C. Vogt, under revision.

4. D. Sinausia, N. Zisser, T. K. Slot, D. Eisenberg, F. Meirer, C. Vogt, under revision. Preprint available at: doi:10.26434/chemrxiv-2024-pzpd0

מארגן הסמינר: ד"ר ברק הירשברג