Probing the dynamics of CO2 electrolysis with X-rays and Raman spectroscopy

Prof. Ward van der Stam

Assistant professor, Inorganic Chemistry and Catalysis, Utrecht University, The Netherlands

Time and Location: 10:45-11:45, 25th November 2022, room G.US.025, Groenenborger Campus, Groenenborgerlaan 171, 2020, Antwerpen
Organizer: NANOlab Center of Excellence, University of Antwerp

The electrocatalytic reduction of CO2 (CO2RR) into valuable base chemicals and fuels is a very complex reaction that depends on the intimate relation between catalyst structure and external reaction conditions.[1] Despite considerable progress over the past few years, it is evident that the precise identification of the active sites of the electrocatalyst under operation remains a challenge, which hinders the rational design and industrial application of advanced electrocatalysts for eCO2RR. For this purpose, in situ characterization techniques are required that probe the catalyst structure, from bulk to surface, with improved time and space resolution. In this presentation, I will discuss how we deploy in situ time-resolved Raman spectroscopy (TR-SERS) to investigate the electrocatalytic activation of CO2 and the dynamic chemical structure of the electrode surface.[2] We have combined TR-SERS with cyclic voltammetry, chronoamperometry and pulsed electrolysis to study the time- & potential-dependent behavior of the electrode surface and the adsorbed species.[3] Furthermore, we deployed TR-SERS mapping to elucidate spatiotemporal heterogeneities of copper electrodes at work.[4] Finally, I will show the utilization of TR-SERS and in situ X-ray characterization techniques to couple the structure of the electrocatalyst to the performance for well-defined nanoparticle electrodes.[5]

[1] S. Nitopi et al. Chem. Rev. 2019, 119, 7610
[2] H. An et al. Angew. Chem. Int. Ed. 2021, 60, 16576
[3] J. de Ruiter et al. J. Am. Chem. Soc. 2022, 144, 15047
[4] H. An et al. submitted
[5] S. Yang et al. submitted & in preparation

Ward van der Stam is a tenure track assistant professor at Utrecht University since June 2019. He obtained his PhD in 2016 from Utrecht University, after which he did postdoctoral research at TU Delft. His expertise is colloidal nanoparticle synthesis and spectroelectrochemistry. Currently, the research team combines colloidal nanoparticle synthesis and multiscale (in situ) characterization to understand and steer the electrocatalytic CO2 reduction reaction to value-added chemicals and fuels. For this purpose, X-ray characterization techniques are used to study the catalyst structure, whereas vibrational spectroscopy is employed to study adsorbed reaction intermediates at the catalyst surface. The overarching goal is to establish structure-performance relationships for CO2 conversion electrocatalysts.