Yao Yang1,David Muller2,Hector Abruna2,Peidong Yang1
UC Berkeley1,Cornell University2
Yao Yang1,David Muller2,Hector Abruna2,Peidong Yang1
UC Berkeley1,Cornell University2
One of the outstanding grand challenges facing energy materials is to directly resolve the complex nature of active structures and capture real-time “<i>movies</i>” of reaction dynamics under operating conditions. The need for such fundamental understanding has stimulated the development of <i>operando</i>/<i>in situ</i> methods, which have greatly enhanced our ability to establish <i>operando </i>(operating) structure-property relationships of energy materials.<br/>In this presentation, I will introduce our recent progress on developing <i>operando </i>electrochemical liquid-cell scanning transmission electron microscopy (EC-STEM), which simultaneously enables quantitative electrochemistry on microelectrodes and quantitative STEM based imaging, diffraction and spectroscopy. <i>Operando</i> electrochemical 4D-STEM in liquid has shown great potentials to interrogate complex structures of active sites of energy materials at solid-liquid interfaces. In particular, I will introduce two examples on dynamic Cu underpotential deposition at nanocrystal surfaces and counterintuitive cathodic (reductive) corrosion processes. I will present my latest work on multimodal <i>operando</i> 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 CO<sub>2</sub> electroreduction.<br/><b>References:</b><br/>1. Yang, Y., Muller, D., Abruna, H. Yang, P. et al. <i>Operando</i> Studies Reveal Active Cu Nanograins for CO<sub>2</sub> Electroreduction. <b><i>Nature</i></b> 2023, 614, 262.<br/>2. Yang, Y., Muller, D., Abruna, H. Elucidating Cathodic Corrosion Mechanisms with <i>Operando</i> Electrochemical Transmission Electron Microscopy. <b><i>J. Am. Chem. Soc</i></b>. 2022, 144, 15698.<br/>3. Yang, Y., Muller, D., Abruna, H. et al. Metal Monolayers on Command: Underpotential Deposition at Nanocrystal Surfaces: A Quantitative <i>Operando</i> Electrochemical Transmission Electron Microscopy Study. <b><i>ACS Energy Lett.</i> </b>2022, 7, 1292.<br/>4. Yang, Y., Yang, P. et al. <i>Operando </i>Resonant Soft X-ray Scattering Studies of Chemical Environment and Interparticle Dynamics of Cu Nanocatalysts for CO2 Electroreduction. <b><i>J. Am. Chem. Soc</i></b><i>. </i>2022, <i>144</i>, 8927.