Webinar #9 - E-chem for TEM 101: E-chem for TEM: Studying Catalysts, Part 3

DR. YAO YANG | University of California, Berkeley (Miller Fellow 2021-2024); Cornell University (PhD 2021)
In this talk, I will present my latest work on multimodal operando studies of combining EC-STEM and correlative synchrotron based X-ray methods to elucidate the longstanding enigmatic nature of Cu active sites as Cu nanograins for selective CO2 electroreduction. I will introduce our recent progress on developing operando electrochemical liquid-cell scanning transmission electron microscopy (EC-STEM), which simultaneously enables quantitative electrochemistry on microelectrodes and quantitative STEM based imaging, diffraction and spectroscopy. Operando electrochemical 4D-STEM in liquid has shown great potentials to interrogate complex structures of active sites of energy materials at solid-liquid interfaces. Synchrotron based operando electrochemical resonant soft X-ray scattering (EC-RSoXS), based on the same liquid-cell holder as the EC-STEM setup, provides complementary information on chemical environment and interparticle dynamics of nanoparticle ensemble catalysts. This study also points out the need for rigorous examination of beam induced effects (both electrons and photons) on samples in liquid. We anticipate that the continuous advances in analytical techniques will pave the way for multimodal operando electron microscopy and X-ray methods to become indispensable, broadly available tools, for understanding interfacial reaction mechanisms for the broad chemistry and energy materials communities.

Key Publications:
1. Yang, Y., Muller, D., Abruña, H. Yang, P. et al. Operando Studies Reveal Active Cu Nanograins for CO2 Electroreduction. Nature 2023, 614, 262.
2. Yang, Y., Yang, P. et al. Operando Resonant Soft X-ray Scattering Studies of Chemical Environment and Interparticle Dynamics of Cu Nanocatalysts for CO2 Electroreduction. J. Am. Chem. Soc. 2022, 144, 8927.